Physical Science

Physical Science Formation of Heavy Elements First Edition, 2020

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Published by the Department of Education Secretary: Leonor Magtolis Briones Undersecretary: Diosdado M. San Antonio

Development Team of the Module

Writers: Rose Ann Q. Abuel Editors: Priscilla D. Domino Felipa A. Morada Reviewers: Elmer C. Bobis, Rogelio D. Canuel Illustrator: Geselle A. Teaňo Layout Artist: Elsie R. Reyes, Pamela A. Lalusin, Mary Grace L. Asa

Management Team: Wilfredo E. Cabral, Regional Director Job S. Zape Jr., CLMD Chief Elaine T. Balaogan, Regional ADM Coordinator Susan DL. Oribiana, Schools Division Superintendent Catherine V. Maranan, Assistant Schools Division Superintendent Lorna R. Medrano, CID Chief Edita T. Olan, EPS-in-Charge, LRMS Editha M. Malihan, EPS

Department of Education – RegionIV-A CALABARZON

Office Address: Gate 2 Karangalan Village,Barangay San Isidro Cainta, Rizal 1800 Telefax: 02-8682-5773/8684-4914/8647-7487 E-mail Address: [email protected]/[email protected]

Physical Science Formation of Heavy Elements

Introductory Message For the facilitator:

Welcome to the Physical Science Alternative Delivery Mode (ADM) Module on

Formation of Heavier Elements!

This module was collaboratively designed, developed and reviewed by educators both from public and private institutions to assist you, the teacher or facilitator in helping the learners meet the standards set by the K to 12 Curriculum while overcoming their personal, social, and economic constraints in schooling.

This learning resource hopes to engage the learners into guided and independent learning activities at their own pace and time. Furthermore, this also aims to help learners acquire the needed 21st century skills while taking into consideration their needs and circumstances.

In addition to the material in the main text, you will also see this box in the body of the module:

Notes to the Teacher This contains helpful tips or strategies that will help you in guiding the learners.

As a facilitator, you are expected to orient the learners on how to use this module. You also need to keep track of the learners' progress while allowing them to manage their own learning. Furthermore, you are expected to encourage and assist the learners as they do the tasks included in the module.

For the learner: Welcome to the Physical Science Alternative Delivery Mode (ADM) Module on Formation of Heavier Elements! The hand is one of the most symbolic parts of the human body. It is often used to depict skill, action and purpose. Through our hands, we may learn, create and accomplish. Hence, the hand in this learning resource signifies that as a learner, you are capable and empowered to successfully achieve the relevant competencies and skills at your own pace and time. Your academic success lies in your own hands! This module was designed to provide you with fun and meaningful opportunities for guided and independent learning at your own pace and time. You will be enabled to process the contents of the learning resource while being an active learner. This module has the following parts and corresponding icons:

What I Need to Know This will give you an idea of the skills or

competencies you are expected to learn in the module.

What I Know This part includes an activity that aims to

check what you already know about the lesson to take. If you get all the answers correctly (100%), you may decide to skip this module.

What’s In This is a brief drill or review to help you link

the current lesson with the previous one.

What’s New In this portion, the new lesson will be

introduced to you in various ways such as a story, a song, a poem, a problem opener, an activity or a situation.

What is It This section provides a brief discussion of the

lesson. This aims to help you discover and understand new concepts and skills.

What’s More This comprises activities for independent

practice to solidify your understanding and skills of the topic. You may check the answers to the exercises using the Answer Key at the end of the module.

What I Have Learned This includes questions or blank

sentence/paragraph to be filled in to process what you learned from the lesson.

What I Can Do This section provides an activity which will

help you apply your new knowledge or skill into real life situations or concerns.

Assessment This is a task which aims to evaluate your

level of mastery in achieving the learning competency.

Additional Activities In this portion, another activity will be given

to you to enrich your knowledge or skill of the lesson learned. This also tends retention of learned concepts.

Answer Key This contains answers to all activities in the

module.

At the end of this module you will also find:

References This is a list of all sources used in developing this module.

The following are some reminders in using this module: 1. Use the module with care. Do not put unnecessary mark/s on any part of the module. Use a separate sheet of paper in answering the exercises. 2. Don’t forget to answer What I Know before moving on to the other activities included in the module. 3. Read the instruction carefully before doing each task. 4. Observe honesty and integrity in doing the tasks and checking your answers. 5. Finish the task at hand before proceeding to the next. 6. Return this module to your teacher/facilitator once you are through with it. If you encounter any difficulty in answering the tasks in this module, do not hesitate to consult your teacher or facilitator. Always bear in mind that you are not alone. We hope that through this material, you will experience meaningful learning and gain deep understanding of the relevant competencies. You can do it!

Week

What I Need to Know

This module will walk you through the beginning of everything. It focuses on how some elements today were formed as stars were born right after the universe existed. You will be provided with activities such as filling out graphic organizer, reading story board and illustrations which make you remember the lesson. Make sure to answer the pretest first before going through this module and the posttest at the end of the module.

The module consists of:  Lesson 1 – Stellar Nucleosynthesis: Rise of the Stars!

After going through this module, you are expected to: 1. explain stellar nucleosynthesis; 2. describe the different stages of life cycle of stars; 3. cite the different heavy elements formed in each stages of star cycle

Have you ever wondered what stars are made of? What keeps them shine so bright? Well, this module will help you understand some of the important concepts about stars. Are you ready? Let’s go!

What I Know

Choose the letter of the best answer in each item and write it on a separate sheet of paper.

1. The accepted theory about the origin of the universe which accounts for its continuous expansion and the probable existence of a primordial atom. a. big bang theory c. steady state theory b. divine creation theory d. oscillating theory

2. The following are light elements EXCEPT; a. helium c. lithium b. hydrogen d. iron

3. The term used to describe the process which formed the elements in the universe is: a. generation c. nucleosynthesis b. genesis d. synthesis

4. Light elements such as hydrogen and helium are formed through the process of ______nucleosynthesis. a. big bang c. stellar b. fusion d. supernova

5. Which element is the lightest and at the same time the most abundant in universe? a. hydrogen c. lithium b. helium d. iron

6. A reaction in which two or more nuclei combine to form heavier nuclei. a. combustion c. nuclear fusion b. nuclear fission d. nuclear synthesis

7. What element is primarily formed when three atoms of helium are fused through the tri-alpha process? a. carbon c. oxygen b. hydrogen d. silicon

8. Which of the following elements DOES NOT belong to the group? a. beryllium c. iron b. silicon d. oxygen

9. The process in which elements are formed at the center of a star. a. big bang nucleosynthesis c. stellar nucleosynthesis b. nuclear fusion d. supernova nucleosynthesis

10. Elements heavier than Iron are formed through______. a. big bang nucleosynthesis c. stellar nucleosynthesis b. nuclear fusion d. supernova nucleosynthesis

11. The element that is formed when Carbon atom is combined with Helium atom: a. magnesium c. oxygen b. neon d. silicon

12. Average stars have longer life span than massive stars. This is because_____; a. they have less fuel to burn c. they burn their fuel at faster rate b. they have more fuel to burn d. they burn their fuel at slower rate

13. Our sun is in what phase of its life cycle? a. main sequence star c. red giant b. planetary nebula d. white dwarf

14. Which of the following contains only heavy elements? a. carbon, lithium, neon b. carbon, silicon, magnesium c. carbon, beryllium, helium d. helium, carbon, hydrogen

15. In which stage do massive stars explode and release large amount of energy? a. main sequence b. protostar c. super nova d. white dwarf

Lesson Stellar Nucleosynthesis: Rise 1 of the Stars!

The world where we live today is just a small part of our universe. In your previous science lessons, you have learned different theories about the origin of the universe that led to the formation of galaxies, solar system and other heavenly bodies. This lesson will focus on one of those wonderful things in outer space, the stars. Although stars are millions of light years away from us, we can still see them twinkling in the night sky. Let’s find out how they emit light and what keeps them shining for a long time.

What’s In

Scientists believe that the formation of the universe began through the explosion of a primordial atom which happened approximately 13.7 billion years ago. The origin of the universe is described by the Big Bang theory which was introduced by Edwin Hubbl e. In 1929, Hubble demonstrated that all celestial objects in the universe move away from each other.

Right after Big Bang, protons and neutrons combined and formed light elements Hydrogen and Helium through the process of Big Bang Nucleosynthesis. Other light elements such as Lithium and Beryllium were also formed during this process.

What’s New

Stellar Nucleosynthesis The word “stellar” means star and the formation of elements in the center of the star is called stellar nucleosynthesis. Carl Sagan said that “We are made of star stuff.” What did he mean by that? If we know how some important heavy elements were formed same as stars, that maybe a clue. Label the sequence of star life cycle. Use the hints/clues found in the table below this diagram.

Star Life Cycle

1. ______

2. ______

3. ______

8. _____ 4. ______

9. _____ 5. ______

10. ______7. ______6. ______

Average Star Massive Star

Hints/ Clues Average Star 1. The star is unable to generate heat when it runs out of hydrogen in its core leading to its contraction and expansion. It cools down and glows red. The Helium fused into Carbon. The star is now RED GIANT 2. Red giant star becomes exhausted of nuclear fuel, the outer material is blown off into space leaving the inert Carbon. The remnant is known as WHITE DWARF. 3. Giant cloud of gas and dust known as NEBULA. 4. It is formed from nebula due to the gravity that pulled Hydrogen gas together until it spins faster and faster and becomes ignited. A PROTOSTAR rises. 5. MAIN SEQUENCE STAR starts to form when nuclear fusion occurs at the core of the star, it begins to contract, glow and become stable. Hydrogen is converted into Helium. 6. This is said to be the remain of the white dwarf that cooled down and no longer emits light and heat. The hypothetical BLACK DWARF.

Massive star 1. It is believed that a NEUTRON STAR is formed from supernova explosion. This is also the smallest star 2. Explosion of star or SUPERNOVA releases large amount of energy. Because of that, elements are dispersed into the space. 3. BLACK HOLE is a region in space where gravity is too strong that no matter can escape from it. 4. A more massive main sequence star evolves, cools and expands faster than low mass star and will turn into RED SUPER GIANT star, the largest known star. Carbon fusion still occurs and Oxygen formed.

Notes to the Teacher

 Guide them in this activity and clarify any misconceptions.  The teacher can also ask the students to illustrate the stages of star cycle using their art materials in a separate bond paper for better retention.

What is It

Were you able to label all the stages of star? Review the hints/clues in the previous activity. You will notice that following the sequence will reveal what happens in each stage of star.

To understand further, answer the following questions below.

1. What element from space is pulled by gravity and turned into a protostar? ______

2. What will happen if a low mass main sequence star runs out of hydrogen fuel? ______

3. How are heavy elements such as Carbon, Oxygen and Neon formed during star formation? ______

4. Why is it impossible for any matter such as light and radiation to escape from a black hole? ______

5. Why do you think massive star has shorter life span than average stars? ______

Look at the diagrams below in order to understand how stars are formed into different stages because of nuclear fusion (combination of nuclei to form heavier one) among heavy elements.

The diagram shows the proton-proton chain reaction in a main sequence star. In this process, the average star gets its energy and convert Hydrogen into

Helium. It starts with a proton and a neutron which fuse together to form deuterium. When another proton collides with deuterium, Helium-3 is formed. Collision between the Helium-3 atom with another helium-3 forms Helium-4.

The case is different for

massive stars (eight times the mass of our sun). These stars undergo CNO (Carbon, Nitrogen, Oxygen) cycle to convert

Hydrogen into Helium. You can see at the left how Carbon-12 fused with proton (H) and form

Nitrogen-13. Nitrogen-13 undergoes beta decay to form Carbon-13. Carbon- 13 captures proton (H) and Nitrogen-14 is formed.

Nitrogen-14 captures proton to produce Oxygen- 15, and Oxygen-15 undergoes beta decay that

forms Nitrogen-15. The Nitrogen-15 fused with proton gives off Helium to generate the stable atom of Carbon-12. Then the

process repeats again.

Tri alpha process happens in red giant star once they leave the stage of main sequence star. This is how three Helium-4 are converted into Carbon.

A star accumulates more mass and continues to grow into red super giant. Alpha particle fusion happens at its core and creates more heavy elements until Iron. This is known as the Alpha ladder process.

How do elements heavier than Iron form? As the energy at the core of the star decreases, nuclear fusion cannot produce elements higher than Iron. A different pathway is needed for heavier elements to be formed. Neutron capture, a neutron is added to a seed nucleus. Below is the representation of how neutron is captured, and a heavier nucleus is formed.

Example:

Neutron capture can be slow or rapid;

a. S-process or slow process happens when there is a slow rate of capturing neutron while there is a faster

rate of radioactive decay hence increasing the proton by 1. Example:

b. R-process or rapid process means that there is faster

rate of capturing neutron before it undergoes radioactive decay thus, more neutrons can be combined in the nucleus. This is what happens in a supernova forming heavier elements than Iron with the process known as supernova nucleosynthesis.

Example:

The explosion of star or supernova is believed to

be the source of other elements heavier than Iron. During the explosion, these heavy elements are dispersed into the space. Aside from Hydrogen and Helium in space, other evidence

of star formation is the energy emitted during nuclear reaction which includes ultraviolet, infrared, X-ray, radio wave and microwave.

What’s More

Match the terms in column A with its description in Column B

A B ______1. Alpha ladder process a. There is faster rate of capturing neutron before it undergoes ______2. Big bang nucleosynthesis radioactive decay ______3. CNO cycle b. Nuclear fusion that happens in red

______4. Neutron capture super giant star and creates more heavy elements until Iron. ______5. Proton- proton chain c. Happens when there is a slow rate ______6. R- process of capturing neutron while there is

______7. S- process a faster rate of radioactive decay d. Process wherein light elements ______8. Stellar Nucleosynthesis such as Helium and Hydrogen ______9.Supernova form. Nucleosynthesis e. This is how three Helium-4 is ______10. Tri alpha process converted into Carbon in red giant

star f. A process where elements heavier than Iron are formed. g. Nuclear fusion reaction where Hydrogen is converted to Helium h. Addition of neutron to form heavier nuclei i. Process by which elements are created within the star j. This happens in massive star which convert Hydrogen into Helium.

What I Have Learned

Read the paragraph then fill in the blanks with the correct word/s.

It all starts with 1. ______, cloud of gas and dust particle in outer space. Due to the force of gravity, the 2. ______gas is pulled together and eventually became a protostar. Nebular fusion occurs at the center of the protostar and becomes stable. During this time, hydrogen is converted into 3. ______forming main sequence star. The size of the star can be average or massive. A massive main sequence star that runs out of hydrogen fuel will begin to expand and cool down. This is 4. ______, the collective term for massive stars in the universe. The red super giant continues to fuse with heavy elements and stops when 5. ______is converted in the core of the star. At this point, red super giant will become a supernova after hundreds of years.

What I Can Do

Now you have learned how stars are formed, go through their lifespan and how each stage of the life of a star leads to formation of elements. There are many processes that stars have to undergo before they evolve from one stage to another. For your next task, you will write a story which relates the events of your life from past, present and future to the life cycle of a star. Use also those elements which could symbolize something or anything in your story. (Use another sheet of paper for this task). ______

Rubrics for Story of Your Life

Criteria Excellent Fair Poor (5pts) ( 3pts) (1pt)

Work shows time, Overall effort effort and neatness that Work shows time Lacks effort and enhances the and effort put into cleanliness overall written it output.

The student's The project output contains contains No background or background and discussion of contextual Background context and shows world events but it information is context how world events is unclear how included. have significantly they have affected affected his/her the student's life. life.

The student does The student The student not commit error commits 1- 3 commits more Grammar and when it comes to grammar mistakes than 4 mistakes in Spelling grammar and and spelling. grammar and spelling. spelling

Student includes Student includes Information information about very few details. included is not

birth, friends, Output is related to the task Content family, hobbies somewhat tied up or no attempt was and is able to tie with the topic made. his/her story to the topic given.

Assessment

Multiple Choice. Choose the letter of the best answer. Write the chosen letter on a separate sheet of paper.

1. Which of the following is NOT an evidence of star formation? a. hydrogen c. infrared Radiation b. helium d. rocks

2. Star’s energy is produced by which process? a. combustion c. nuclear fission b. decomposition d. nuclear fusion

3. If the sun reaches the end of red giant phase, it will evolve into a ______. a. black hole c. red super giant b. supernova d. white dwarf

4. A category which includes the largest stars in the universe. a. main sequence star c. red super giant b. red giant d. white dwarf

5. Which of the following elements are major components of star? a. carbon and oxygen c. hydrogen and carbon b. helium and carbon d. hydrogen and helium

6. Which of the following statements is FALSE? a. The core of red giant star is made up of carbon b. The average star has shorter life span c. The more massive the star is the faster it burns its fuel d. No elements heavier than Iron can be produced in a massive star

7. Which is the first stage of a star’s life cycle? a. black hole c. protostar b. nebula d. white dwarf

8. In main sequence star, Hydrogen atoms fuse to form Helium. Helium is then converted into ______at its core. a. carbon c. neon b. iron d. silicon

9. This element is produced through Big Bang nucleosynthesis and is considered as the second most abundant element in the universe. a. carbon c. hydrogen b. helium d. oxygen

10. What object is formed from gas and dust particles which are pulled together by gravity wherein no nuclear fusion has happened yet? a. nebula c. protostar b. main sequence star d. red supergiant star

11. Who stated that we are made of star stuff? a. Carl Sagan c. Galileo Galilei b. Edwin Hubble d. Stephen Hawking

12. What is the sign that a protostar will transform into the next stage? a. When the it starts to spin faster b. When it starts to glow c. When Hydrogen nuclear fusion begins d. When it increases temperature igniting the Hydrogen

13. When does a star become unstable? a. When it runs out of fuel b. When it contracts and expands c. When its core is converted to Iron d. When the outer shell of star is pulled by the gravity from the center

14. Which elements fuse together to form Iron? a. carbon fusion c. magnesium fusion b. neon fusion d. silicon fusion

15. This is a huge luminous ball of hot gas such as Hydrogen and Helium. a. comet c. planet b. moon d. star

Additional Activities

On this activity, you will see a star with the topic written on its center. Fill out the parts of the stars with concepts that you have learned in this module.

7 2

Star Formation

6 3

5 4

Answer Key

D 15. C 15.

D 14. B 14.

A 13. A 13.

C 12. B 12.

A 11. C 11.

E 10. C 10. D 10.

F 9. B 9. C 9.

I 8. A 8. A 8.

C 7. B 7. A 7.

A 6. 9. B 6. C 6.

G 5. 8. D 5. A 5.

H 4. 7. C 4. A 4.

J 3. 6. D 3. C 3.

D 2. 5. D 2. D 2.

4. B D 1. A 1.

Assessment More What’s Know I What

dwarf Black 10.

dwarf White 9.

giant Red 8.

star Neutron 7.

hole Black 6.

Supernova 5. Iron 5.

giant super Red 4. giant super Red 4.

star sequence Main 3. Helium 3.

Protostar 2. drogen Hy 2.

Nebula 1. Nebula 1.

New What’s Learned Have I What

References

Dhaliwal, J and Moore,J. (n.d).Stellar Nucleosynthesis and The Periodic Table. Retrieved from https://earthref.org/SCC/lessons/2012/nucleosynthesis/#materials

National Aeroautics and Space Administration. (2015, May 7).Imagine the Universe. Retrieved from https://imagine.gsfc.nasa.gov/educators/lifecycles/LC_main_p2.html

The Elements: Forged in Stars.(n.d). Retrieved from https://www.pbslearningmedia.org/resource/ess05.sci.ess.eiu.fusion/the- elements-forged-in-stars/

Toogood, O (n.d).Hubbles Law and the Big Bang. Retrieved from http://www.alevelphysicsnotes.com/astrophysics/big_bang.html# Cain, F. (2009, February 5). Red Super Giant Star. Retrieved from https://www.universetoday.com/

Quipper. (n.d). Nucleosynthesis: The beginning of Elements. Retrieved from https://link.quipper.com/en/organizations/547ff9a8d2b76d0002001cf8/cu rriculum#curriculum

Cantor, K. (n.d). Asrtonomy Portfolio. Retrived from https://sites.google.com/a/wnesu.com/astronomy-portfolio-kenny- cantor/big-bang-theory

Wiess, A. (2006). “Big Bang Nucleosynthesis: Cooking up the first Light Elements”. Retrieved from https://www.einstein-online.info/en/spotlight/bbn/

Strassler, M. (2013, March 4). What Holds Nuclei Together?. Retrived from https://profmattstrassler.com/articles-and-posts/particle-physics- basics/the-structure-of-matter/the-nuclei-of-atoms-at-the-heart-of- matter/what-holds-nuclei-together/

Esiegel. (2014, February 28). Burn Baby Burn! https://scienceblogs.com/startswithabang/2014/02/28/ask-ethan-26- burn-baby-burn

Canoy, W.Z. ( 2019, November 10). We Are all Made of Star Stuff. Retrieved from https://www.facebook.com/notes/physical-science/lesson-2-we-are-all- made-of-star-stuff-formation-of-the-heavy-elements/3024639240885614/

For inquiries or feedback, please write or call:

Department of Education - Bureau of Learning Resources (DepEd-BLR)

Ground Floor, Bonifacio Bldg., DepEd Complex Meralco Avenue, Pasig City, Philippines 1600

Telefax: (632) 8634-1072; 8634-1054; 8631-4985

Email Address: [email protected] * [email protected]

PhysicalPhysical

ScienceScience Quarter 1

Physical Science Concept of Atomic Number Led to the Synthesis of New Elements in the Laboratory First Edition, 2020

Published by the Department of Education Secretary: Leonor Magtolis Briones Undersecretary: Diosdado M. San Antonio

Development Team of the Module

Writers: Francis Darril O. Albo Editors: Priscilla D. Domino Felipa A. Morada Reviewers: Rogelio D. Canuel, Elmer C. Bobis, Felipa A. Morada Illustrator: Geselle A. Teaño Layout Artist: Elsie R. Reyes, Pamela A. Lalusin, Mary Grace L. Asa Management Team: Wilfredo E. Cabral, Regional Director Job S. Zape Jr., CLMD Chief Elaine T. Balaogan, Regional ADM Coordinator Susan DL. Oribiana, Schools Division Superintendent Lorna R. Medrano, CID Chief Edita T. Olan, EPS in-Charge, LRMS Editha M. Malihan, EPS

Department of Education – Region IV-A CALABARZON

Office Address: Gate 2 Karangalan Village, Barangay San Isidro Cainta, Rizal 1800 Telefax: 02-8682-5773/8684-4914/8647-7487 E-mail Address: [email protected]/[email protected]

Physical Science Concept of Atomic Number Led to the Synthesis of New Elements in the Laboratory

Introductory Message

For the facilitator:

Welcome to the Physical Science Grade 11 Alternative Delivery Mode (ADM) Module on Concept of Atomic Number Led to the Synthesis of New Elements in the Laboratory!

In addition to the material in the main text, you will also see this box in the body of the module:

Notes to the Teacher This contains helpful tips or strategies that will help you in guiding the learners.

For the learner:

Welcome to the Physical Science Grade 11 Alternative Delivery Mode (ADM) Module on Concept of Atomic Number Led to the Synthesis of New Elements in the Laboratory!

The hand is one of the most symbolic parts of the human body. It is often used to depict skill, action and purpose. Through our hands we may learn, create and accomplish. Hence, the hand in this learning resource signifies that as a learner, you are capable and empowered to successfully achieve the relevant competencies and skills at your own pace and time. Your academic success lies in your own hands!

This module was designed to provide you with fun and meaningful opportunities for guided and independent learning at your own pace and time. You will be enabled to process the contents of the learning resource while being an active learner.

This module has the following parts and corresponding icons:

What I Need to Know This will give you an idea of the skills or

competencies you are expected to learn in the module.

What I Know This part includes an activity that aims to

check what you already know about the lesson to take. If you get all the answers correct (100%), you may decide to skip this module.

What’s In This is a brief drill or review to help you link

the current lesson with the previous one.

What’s New In this portion, the new lesson will be

introduced to you in various ways such as a story, a song, a poem, a problem opener, an activity or a situation.

What is It This section provides a brief discussion of the

lesson. This aims to help you discover and understand new concepts and skills.

What’s More This comprises activities for independent

practice to solidify your understanding and skills of the topic. You may check the answers to the exercises using the Answer Key at the end of the module.

What I Have Learned This includes questions or blank

sentence/paragraph to be filled in to process what you learned from the lesson.

What I Can Do This section provides an activity which will

help you apply your new knowledge or skill into real life situations or concerns.

Assessment This is a task which aims to evaluate your

level of mastery in achieving the learning competency.

Additional Activities In this portion, another activity will be given

to you to enrich your knowledge or skill of the lesson learned. This also tends retention of learned concepts.

Answer Key This contains answers to all activities in the

module.

At the end of this module you will also find:

References This is a list of all sources used in developing this module.

The following are some reminders in using this module:

1. Use the module with care. Do not put unnecessary mark/s on any part of the module. Use a separate sheet of paper in answering the exercises. 2. Don’t forget to answer What I Know before moving on to the other activities included in the module. 3. Read the instruction carefully before doing each task. 4. Observe honesty and integrity in doing the tasks and checking your answers. 5. Finish the task at hand before proceeding to the next. 6. Return this module to your teacher/facilitator once you are through with it. If you encounter any difficulty in answering the tasks in this module, do not hesitate to consult your teacher or facilitator. Always bear in mind that you are not alone.

We hope that through this material, you will experience meaningful learning and gain deep understanding of the relevant competencies. You can do it!

Week

What I Need to Know

This module is especially designed for you. It will help you track the development of your understanding on how the concept of atomic number led to the synthesis of new elements in the laboratory.

To make learning easy for you, the module provides activities to develop your curiosity on how the concept of atomic number led to the synthesis of new elements in the laboratory

The scope of this module permits it to be used in different learning situations. The language used recognizes the numerous vocabulary levels of students. The lessons are arranged to follow the standard sequence of the course. But the order in which you read them can be changed to correspond with the textbook you are using.

After going through this module, you are expected to:

1. explain how the concept of atomic number led to the synthesis of new elements in the laboratory; 2. identify the different elements formed after the process of synthesis; 3. realize the importance of the atomic number in identifying the new elements identity in the periodic table.

What I Know

Directions: Choose the letter of the best answer. Write the chosen letter on a separate sheet of paper.

1. It is a device that is used to speed up the protons to overcome the repulsion between the protons and the target atomic nuclei by using magnetic and electrical fields. a. Spectroscopy c. Particle Accelerator b. Particle Decelerator d. Microscope

2. He created a classification of elements based on their atomic weight. a. Ernest Rutherford c. Robert Millikan b. John Dalton d. Dmitri Mendeleev 3. It is a one-dimensional point which contains a huge mass in an infinitely small space. a. Nucleosynthesis c. Singularity b. Dilation d. R-process 4. He noticed that shooting electrons at elements caused them to release x-rays at unique frequencies. a. Dmitri Mendeleev c. Henry Moseley b. Robert Millikan d. Emilio Serge 5. He synthesized element with atomic number 43 using a linear particle accelerator. a. Ernest Rutherford c. Dmitri Mendeleev b. Ernest Lawrence d. John Dalton

6. This is known as the origin and production of heavy elements. a. Stellar Nucleosynthesis c. R-Process b. Primordial Nucleosynthesis d. Supernova Nucleosynthesis

7. This is known as the origin of light elements. a. Stellar Nucleosynthesis c. R-Process b. Primordial Nucleosynthesis d. Supernova Nucleosynthesis

8. The process that can produce elements up to bismuth (atomic number 83). a. Nuclear Fission c. S Process b. R-Process d. Stellar Nucleosynthesis

9. This is also known as Nucleosynthesis. a. S Process c. Nuclear Fission b. R-Process d. Proton-Proton Reaction

10. This occurs in the main sequence of stars. a. Stellar Nucleosynthesis c. R-Process b. Primordial Nucleosynthesis d. Supernova Nucleosynthesis

11. It is also known as nuclear fusion and the formation of new nuclei actions in the early stages of development of the universe. a. Nucleosynthesis c. R-Process b. S-Process d. Singularity

12. In this process, there’s a buildup of a very heavy isotope, then as beta-decays occur, you march up in atomic number and produce heavy product. a. S Process c. Nuclear Fission b. R-Process d. Proton-Proton Reaction

13. He successfully carried out a nuclear transmutation reaction, a process of transforming one element or isotope into another element. a. James Chadwick c. Dmitri Mendeleev b. Henry Moseley d. Ernes Rutherford

14. It was created by bombardment of molybdenum by deuterons (heavy hydrogen, H12), by Emilio Segre and Carlo Perrier in 1937. a. Oxygen c. Technetium b. Helium d. Uranium

15. These are elements with atomic numbers beyond 103. a. Super Heavy Elements c. Lightest Element b. Gases Elements d. Halogens

Lesson Physical Sciences: Concept of Atomic Number that Led to the Synthesis 6 of New Elements in the Laboratory

The atoms that make up the elements are further composed of tiny particles, the neutron, proton and electron. H and Helium are the elements that exist in the early beginning of the Big Bang. As the Universe expanded and cooled, there was a period of proton-proton chain reaction wherein protons fused into Helium. Red giant cores get past this via the Triple-Alpha process, but the Universe expands right through this possibility and the density/temperature are quickly too low to support synthesis of any additional elements.

What’s In

You learned earlier how all matter in the universe is made from tiny building blocks called atoms. All modern scientists accept the concept of the atom, but when the concept of the atom was first proposed about 2,500 years ago, ancient philosophers laughed at and opposed the idea. It has always been difficult to convince people about the existence of things that are too small to be seen. We will spend some time considering the evidence (observations) that helped convince scientists of the existence of atoms.

Do you have any idea how the different elements on the periodic table were formed, known and identified? Let’s have a short review.

There is what we call Big Bang Theory that has some key stages: Singularity, Inflation, Nucleosynthesis and Recombination: Let us differentiate them. Singularity is a one-dimensional point which contains a huge mass in an infinitely small space, where density and gravity become infinite and space-time curves infinitely, and where the laws of physics as we know them cease to operate. The basic homogeneity in distribution of matter in the universe was established as a consequence of the first phase of inflation. Nucleosynthesis was the nuclear fusion and the formation of new nuclei actions in the early stages of development of the universe. Recombination - the formation of the capture of free electrons by the cations in a plasma.

Notes to the Teacher Let the student explore the process and the history on how elements form using the concept of atomic number.

What’s New

Activity I.I Making Your Own Periodic Table

Make your own periodic table using the hypothetical elements that are given clues. Explain the word/s that will be formed if you arrange the symbols of the elements correctly.

a. P and Pr both have one electron each. Pr has a bigger atomic size. b. Od, Ri, and E are in the same series as P, C, and I. In terms of atomic size, P is the biggest while C is the smallest. E is a metal while I is a non-metal. Od is smaller than Ri in atomic size. c. O has a bigger atomic size than E in the same group. Y is also a bigger atom than C in the same group. R is more nonmetallic than Pe but more metallic than Ti.

What is It

Key Points

 The atomic number is the number of protons (positively charged particles) in an atom.  In 1913, Henry Gwyn-Jeffreys Moseley was an English physicist who demonstrated that the atomic number, the number of protons in an atom, determines most of the properties of an element.  In 1919, Ernest Rutherford successfully carried out a nuclear transmutation reaction a process of transforming one element or isotope into another element.  In 1925, there were four unknown elements in the periodic table that corresponds to atomic numbers 43, 61, 85, and 87. Elements with atomic numbers 43 and 85 were synthesized using particle accelerators.  A particle accelerator is a device that is used to speed up the protons to overcome the repulsion between the protons and the target atomic nuclei by using magnetic and electrical fields. It is used to synthesize new elements.

 Elements with atomic numbers greater than 92 (atomic number of uranium) are called transuranium elements They were discovered in the laboratory using nuclear reactors or particle accelerators.

Dmitri Mendeleev created a classification of elements based on their atomic weight. He found that organizing the elements at the time by their calculated weight demonstrated a periodic pattern of both physical and chemical properties, such as luster, physical state, reactivity to water, and others. Activity 1.1 Making Your Own Periodic Table shows how theoretical elements where arranged according to their atomic weights. For example, H has an atomic mass of 1.00794 amu, which makes hydrogen the lightest element on the periodic table. Hydrogen, H, was named by Laviosier and is the most abundant element on the periodic table. It is followed by He, Li, Be and so on and so fort because atomic weight is used to arrange elements from lightest to heaviest.

By the way, scientist illustrated in the left is Henry Moseley. He was an English physicist and his experiment demonstrated that the major properties of an element are determined by the atomic number, not by the atomic weight, and firmly established the relationship between atomic number and the charge of the atomic nucleus.

Henry Moseley was a researcher at Rutherford’s laboratory.

In 1913, Moseley used Ernest Rutherford’s findings to advance the understanding of the elements and solve the problem with Mendeleev’s periodic table.

Moseley noticed that shooting electrons at elements caused them to release x- rays at unique frequencies. He also noticed that the frequency increased by a certain amount when the “positive charge” of the chosen element was higher.

By arranging the elements based on the square root of the frequency that they emitted, he was able to arrange the elements that approximates their observed properties as proposed by Mendeleev.

Henry Moseley proposed that the elements’ atomic number, or place in the periodic table, was uniquely tied to their “positive charge”, or the number of protons they have. This discovery allowed for a better arrangement of the periodic table, and predicted elements that were not yet discovered. His method of identifying elements by shooting electrons and looking at x-rays became a very useful tool in characterizing elements, and is now called x-ray spectroscopy.

He used X-ray spectroscopy to determine the atomic number of an element. He bombarded a beam of electrons to different elements and measured their X-ray spectral lines. His results clearly showed that frequency of the X-rays given off by an element was mathematically related to the position of that element in the periodic table. The frequency is proportional to the charge of the nucleus, or the atomic number.

When the elements were arranged according to their atomic numbers, there were four gaps in the table. These gaps corresponded to the atomic numbers 43, 61, 85, and 87. These elements were later synthesized in the laboratory through nuclear transmutations.

Discovery of Nuclear Transmutation

In 1919, Ernest Rutherford successfully carried out a nuclear transmutation reaction — a reaction involving the transformation of one element or isotope into another element. The first nuclide to be prepared by artificial means was an isotope of oxygen, 17O. It was made by Ernest Rutherford in 1919 by bombarding nitrogen atoms with α particles: 14N +4α  17O + 1H 7 2 8 1 However, both alpha particles and atomic nuclei are positively charged, so they repel each other. Therefore, instead of using fast-moving alpha particles in synthesizing new elements, atomic nuclei are often bombarded with neutrons (neutral particles) in particle accelerators.

James Chadwick discovered the neutron in 1932, as a previously unknown neutral particle produced along with 12C by the nuclear reaction between 9Be and 4He: 9퐵푒 +4퐻푒  12퐶 + 1푛 4 2 6 0 The first synthesized element that does not occur naturally on the earth, technetium, was created by bombardment of molybdenum by deuterons 2 (heavy hydrogen, 1퐻, by Emilio Segre and Carlo Perrier in 1937:

2 97 1 97 1퐻 +42푀표2 0푛 +43푇푐

The first controlled nuclear chain reaction was carried out in a reactor at the University of Chicago in 1942. One of the many reactions involved was:

235푈 + 1푛 → 87퐵푟 + 146퐿푎 + 31푛 92 0 35 57 0

The Discovery of the Missing Elements

Recall that in 1925, there were four vacancies in the periodic table corresponding to the atomic numbers 43, 61, 85, and 87. Two of these elements were synthesized in the laboratory using particle accelerators. A particle accelerator is a device that is used to speed up the protons to overcome the repulsion between the protons and the target atomic nuclei by using magnetic and electrical fields. It is used to synthesize new elements. In 1937, American physicist Ernest Lawrence was also able to synthesize element with atomic number 43 using a linear particle accelerator. He bombarded molybdenum (Z=42) with fast-moving neutrons. The newly synthesized element was named Technetium (Tc) after the Greek word "technêtos" meaning “artificial.” Tc was the first man-made element.

The bombarding of Mo with deuteron formed technicium which is the first artificially made element.

97 2 97 1 42푀표 +1퐻 43푇푐 + 0푛

In 1940, Dale Corson, K. Mackenzie, and Emilio Segre discovered element with atomic number 85. They bombarded atoms of bismuth (Z=83) with fast-moving alpha particles in a cyclotron. A cyclotron is a particle accelerator that uses alternating electric field to accelerate particles that move in a spiral path in the presence of a magnetic field. Element-85 was named astatine from the Greek word “astatos” meaning unstable.

The two other elements with atomic numbers 61 and 87 were discovered through studies in radioactivity. Element-61 (Promethium) was discovered as a decay product of the fission of uranium while element-87 (Francium) was discovered as a breakdown product of uranium.

The Synthesis of the Elements

The invention of cyclotron paved the way for artificial transmutation of one element into another. The high-energy particles produced by the cyclotron produce heavier nuclei upon hitting heavy target nuclei.

The Universe ran into the Be problem. Red giant cores get past this via the Triple-Alpha process, but the Universe expands right through this possibility and the density/temperature are quickly too low to synthesis any additional elements.

Big Bang Nucleosynthesis

 The oldest stars in the Galaxy are deficient in elements heavier than Helium.  The current record holder has Fe/H about 130,000 times smaller than the solar value.  Not quite down to Big Bang abundances, but we are getting pretty close and still looking.

Chemical Evolution of the Universe

So we need to find the sources of the vast majority of elements in the Periodic Table of elements. We already know about some of the sources.

Chemical Evolution

 Low-mass stars synthesize `new’ He, C, O during the main- sequence, RGB, HB and AGB phases.  These newly produced elements are brought to the surface via convection and redistributed via stellar winds and planetary nebulae into the interstellar medium to be incorporated into later generations of stars.

Chemical Evolution II  For more massive stars, `equilibrium’ fusion reactions produce elements all the way up to Fe.  Freshly made elements are delivered via stellar winds or, sometimes more spectacularly via supernova explosions

Chemical Evolution III

What about the trans-Fe elements? • Equilibrium fusion reactions of light elements don’t proceed past Fe because of Fe’s location at the peak of the curve of binding energy. • However, in certain circumstances, supernovae for example, non- equilibrium reactions can build elements beyond Fe in the Periodic Table. Many of these are radioactive, but some are stable.

Neutron Capture Elements • There are two principle paths to building the elements heavier than Fe. Both use the addition of neutrons to existing `seed’ nuclei (neutrons have no charge so are much easier to add to positively- charged nuclei). S-process (slow addition of neutrons) R-process (rapid addition of neutrons) The S-process • The S-process stands for the Slow addition of neutrons to nuclei. The addition of a no produces heavier isotope of a particular element. However, if an electron is emitted (this is called beta- decay), the nucleus moves one step up the periodic table. • `Slow’ here means that rate of no captures is low compared to the beta-decay rate. • It really is slow. Sometimes hundreds of years go by between neutron captures. The s-process acting in the range from Ag to Sb.

Here a neutron changed into a proton by emitting an electron • The S-process can produce elements up to #83 - Bismuth. There are peaks in the Solar System abundance of heavy elements at 38Sr, 56Ba and 82Pb. These are easily understood in the context of the S- process and `magic’ numbers of neutrons. • The site of the S-process is AGB start during and between shell flashes. The no source is a by-product of C13 and He4 is O16 • 43Tc is an s-process nucleus and proof that it is in operation in AGB stars.

The R-process • The R-process is the Rapid addition of neutrons to existing nuclei. Rapid here means that many neutrons are added before a beta- decay occurs. • First build up a very heavy isotope, then, as beta-decays occur, you march up in atomic number and produce the REALLY HEAVY STUFF. • A big burst of neutrons is needed for the R-process to occur. The most promising place with the right conditions is in a SNII explosion right above the collapsed core.

• We see an overabundance of R-process elements in the oldest stars. As the early chemical enrichment of the Galaxy was through SNII, this is evidence of SNII as the source of r-process elements. • If we look at the Crab Nebula or other SNII remnants we don’t see r- process elements. • We DO see regions of enhanced O, Si, Ne and He which appear to reflect the `onion skin’ structure of the massive star progenitor.

Crab Nebula 1Diagram (How R-Process Occur) https://www.nasa.gov/mission_pages/hubble/multimedia/crab_ nebula.html

The Transuranic Elements

In the 1930s, the heaviest element known was uranium, with an atomic number 92. Early in 1940, Edwin McMillan proved that an element having an atomic number 93could be created. He used a particle accelerator to bombard uranium with neutrons and created an element with an atomic number 93 which he named neptunium.

Transuranic elements are synthetic elements with atomic numbers higher than that of Uranium (Z = 92).

238 1 239 0 92푈 + 0푛 → 93푁푝 + −1훽

Plutonium (Z = 94)

238푈 + 2퐻 → 239푁푝 + 21푛 92 1 93 0

238 239 +1 0 93푁푝 → 94푁푝 + −1훽

At the end of 1940, element-94 was synthesized by Seaborg, McMillan, Kennedy, and Wahl. They bombarded uranium with deuterons (particles composed of a proton and a neutron) in a cyclotron. Element-94 was named plutonium.

Elements with atomic numbers greater than 92 (atomic number of uranium) are called transuranium elements. Hence, neptunium and plutonium are both transuranium elements. They are unstable and decay radioactively into other elements. All these elements were discovered in the laboratory as artificially generated synthetic elements. They are prepared using nuclear reactors or particle accelerators. In the next lesson, you will learn the nuclear reactions involved in the synthesis of these transuranium elements.

Stellar nucleosynthesis

This process creates elements within stars by combining the protons and neutrons together from the nuclei of lighter elements. Fusion inside stars transforms hydrogen into helium, heat, and radiation. Heavier elements are created in different types of stars as they die or explode.

The Superheavy Elements

Superheavy elements are elements with atomic numbers beyond 103. These are produced by bombarding heavy nuclear targets with accelerated heavy projectiles.

Bohrium (Z = 107) – projectile used was Cr

209퐵𝑖 + 54퐶푟 → 261퐵ℎ + 21푛 83 24 107 0

Following are the equations of several nuclear reactions that have important roles in the history of nuclear chemistry:

• The first naturally occurring unstable element that was isolated, polonium, was discovered by the Polish scientist Marie Curie and her husband Pierre in 1898. It decays, emitting particles:

212 208 4 84푃표 → 82푃푏 + 2퐻푒

What’s More

Activity 1.1 Write the nuclear reactions involved in the synthesis of each of the following new elements:

4 a. Curium (Z = 96) was formed by reacting Pu-239 with alpha particles 2He. It has a half-life of 162 days. b. Mendelevium (Z = 101) was formed by reacting En-253 with alpha particles. c. Meitnerium (Z = 109) was formed by cold fusion which involves the combination of Bi and Fe nuclides at ordinary temperature

What I Have Learned

Why do scientists study and synthesize new transuranium elements in the laboratory? What are the uses of these elements?

Create a timeline using illustrations and text showing on how elements form with the concept of atomic number.

Timeline Rubric

Category 10 points 7 points 5 points 3 points Facts were Facts Facts were Facts were accurate were often Content/ accurate for accurate for for most inaccurat Facts all events almost all (~75%) of e for reported on events the events the timeline reported on events reported the reported on on the timeline. the timeline. timeline. Some All graphics All graphics graphics are are are Several Graphics effective and effective, but effective graphics balanced there and their are with text appear to be use not use. too few or is balanced effective. too many. with text use. The overall The overall appearance appearance of the The The Readability of the timeline is timeline is timeline is timeline is somewhat relatively difficult pleasing pleasing and readable. to read. and easy to easy to read. read. The timeline The The timeline contained timeline The contained at least 8-9 contained timeline Requirements 10 events events at least 6-7 contained related to related to events fewer the topic the topic related to than 5 being being the topic events. studied. studied. being studied.

What I Can Do

A. Short Essay (maximum of 3 sentences)

1. Dmitri Mendeleev is often regarded as the Father of the Periodic Table. Would you say that Henry Moseley deserves recognition like him?

2. Explain why the atomic number is called the “fingerprint” of elements.

3. How would you relate alchemy to synthesis of new elements?

Assessment

Directions: Choose the letter of the best answer. Write the chosen letter on a separate sheet of paper. 1. He successfully carried out a nuclear transmutation reaction, a process of transforming one element or isotope into another element. a. James Chadwick c. Dmitri Mendeleev b. Henry Moseley d. Ernest Rutherford

2. This is also known as Nucleosynthesis. a. S Process c. Nuclear Fission b. R-Process d. Proton-proton Reaction

3. This is known as the origin and production of heavy elements. a. Stellar Nucleosynthesis c. R-Process b. Primordial Nucleosynthesis d. Supernova Nucleosynthesis

4. It was created by bombardment of molybdenum by deuterons (heavy 2 hydrogen, 1H)), by Emilio Segre and Carlo Perrier in 1937. a. Oxygen c. Technetium b. Helium d. Uranium\

5. Process that can produce elements up to Bismuth (atomic number = 83). a. Nuclear Fission c. S Process b. R-Process d. S Process

6. This is known as the origin of light elements. a. Stellar Nucleosynthesis c. R-Process b. Primordial Nucleosynthesis d. Supernova Nucleosynthesis

7. It is also known as nuclear fusion and the formation of new nuclei actions in the early stages of development of the universe. a. Nucleosynthesis c. R-Process b. S-Process d. Singularity

8. In this process there’s a buildup of a VERY heavy isotope, then as beta- decays occur, you march up in atomic number and produce heavy product. a. S Process c. Nuclear Fission b. R-Process d. Proton-Proton Reaction

9. These are elements with atomic numbers beyond 103. a. Superheavy elements c. Transition element b. Gases elements d. Halogens

10. This occurs in the main sequence of stars. a. Stellar Nucleosynthesis c. R-Process b. Primordial Nucleosynthesis d. Supernova Nucleosynthesis

11. It is a device that is used to speed up the protons to overcome the repulsion between the protons and the target atomic nuclei by using magnetic and electrical fields. a. Spectroscopy c. Particle Accelerator b. Particle Decelerator d. Microscope

12. He created a classification of elements based on their atomic weight. a. Ernest Rutherford c. Robert Millikan b. John Dalton d. Dmitri Mendeleev

13. It is a one-dimensional point which contains a huge mass in an infinitely small space. a. Nucleosynthesis c. Singularity b. Dilation d. R-process

14. He noticed that shooting electrons at elements caused them to release X-rays at unique frequencies. a. Dmitri Mendeleev c. Henry Moseley b. Robert Millikan d. Emilio Serge

15. He synthesized the 43rd element using a linear particle accelerator. a. Ernest Rutherford c. Dmitri Mendeleev b. Ernest Lawrence d. John Dalton

Additional Activities

Research on the latest instruments used in preparing new elements in the laboratory. What were the instruments used in preparing the newest four elements, nihonium, moscovium, tennessine, and oganesson?

Answer Key

b 15.

c 14. 10n + 266109Mt

c 13. > > — 5826Fe + 20983Bi c.

d 12. Mendeleev.

c 11. Dmitri after named

a 10. Mv is is Mv 10n + 256101Mv

a 9. > — 42He + En 25399 b.

b 8. radioactivity.

a 7. research on natural natural on research

b 6.

done extensive extensive done

c 5.

Pierre Curie who had had who Curie Pierre

c 4.

named after Marie and and Marie after named

a 3.

+ 10n Cm is is Cm 10n +

6Cm 2429 c 2.

> > — 42He + 23994Pu a. d 1.

More What's Assessment

a 15.

c 14.

d 13.

b 12.

a 11.

a 10.

c 9.

c 8.

b 7.

a 6.

b 5.

c 4.

c 3.

d 2.

c 1.

Know I What

References

Coyne, Glynis L. (2012). Lead to Gold, Sorcery to Science: Alchemy and the Foundations of Modern Chemistry. University of North Carolina PIT Journal, 4. Retrieved October 10, 2015 http://pitjournal.unc.edu/article/lead-gold-sorcery-sciencealchemy-and- foundations-modern-chemistry; Famous Scientist Org. “Henry Moseley.” Famous Scientists. famouscientist.org, December 29, 2014. http://www.famousscientists.org/henry-moseley/. Gonzales, Jay. “Synthesis of the New Elements in the Laboratory.” LinkedIn Corporation. SlideShare, December 22, 2017. https://www.slideshare.net/JhayGonzales/synthesis-of-the-new- elements-in-the-laboratory.

“Henry Moseley, the Atomic Number, and Synthesis of Elements.” Teach Together, 2012. http://teachtogether.chedk12.com/teaching_guides/view/283.

Navarro, Mary Grace. “The Atomic Number and the Synthesis of New Elements.” Academia. Academia.edu. Accessed May 22, 2020. https://www.academia.edu/33928561/The_Atomic_Number_and_the_ Synthesis_of_New_Elements.

“The Synthesis of the Elements.” Lick Observatory. Accessed May 23, 2020. http://www.ucolick.org/~bolte/AY4_04/class6_04bwd.pdf.

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Physical Science

Physical Science Polarity of Molecules First Edition, 2020

Published by the Department of Education Secretary: Leonor Magtolis Briones Undersecretary: Diosdado M. San Antonio

Development Team of the Module

Writers: Bayani T. Vicencio, Valeria Amor C. Rosita Editors: Priscilla D. Domino Gertrudes L. Malabanan Reviewers: Rogelio D. Canuel, Elmer C. Bobis, Gertrudes L. Malabanan, Illustrator: Geselle A. Teaňo Layout Artist: Elsie R. Reyes Management Team: Wilfredo E. Cabral, Regional Director Job S. Zape Jr., CLMD Chief Elaine T. Balaogan, Regional ADM Coordinator Helen A. Ramos, Schools Division Superintendent Rhina O. Ilagan, Assistant Schools Division Superintendent Edna U. Mendoza, CID Chief Ronaldo V. Ramilo, EPS-in-Charge, LRMS

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Physical Science Polarity of Molecules

Introductory Message

For the facilitator:

Welcome to the Physical Science Grade 11 Alternative Delivery Mode (ADM) Module on Polarity of Molecules!

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For the learner:

Welcome to the Physical Science Grade 11 Alternative Delivery Mode (ADM) Module on Polarity of Molecules!

The hand is one of the most symbolic part of the human body. It is often used to depict skill, action and purpose. Through our hands we may learn, create and accomplish. Hence, the hand in this learning resource signifies that you as a learner is capable and empowered to successfully achieve the relevant competencies and skills at your own pace and time. Your academic success lies in your own hands!

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skills of the topic. You may check the answers to the exercises using the Answer Key at the end of the module.

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lesson learned. This also tends retention of learned concepts.

This contains answers to all activities in the Answer Key module.

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1. Use the module with care. Do not put unnecessary mark/s on any part of the module. Use a separate sheet of paper in answering the exercises. 2. Don’t forget to answer What I Know before moving on to other activities included in the module. 3. Read the instruction carefully before doing each task. 4. Observe honesty and integrity in doing the tasks and checking your answers. 5. Finish the task at hand before proceeding to the next. 6. Return this module to your teacher/facilitator once you are through with it. If you encounter any difficulty in answering the tasks in this module, do not hesitate to consult your teacher or facilitator. Always bear in mind that you are not alone.

We hope that through this material, you will experience meaningful learning and gain deep understanding of the relevant competencies. You can do it!

Week

What I Need to Know

This module was designed and written with you in mind. It is here to help you determine if a molecule is polar or non-polar. The scope of this module permits it to be used in many different learning situations. The language used recognizes the varied vocabulary level of students. The lessons are arranged to follow the standard sequence of the course. But the order in which you read them can be changed to correspond with the textbook you are now using.

The lesson for this module is about Polarity of Molecules

After going through this module, you are expected to: 1. differentiate polar and nonpolar bonds; 2. determine the polarity of chemical bonds between atoms using the concept of electronegativity; 3. familiarize with the different shapes of molecules; 4. explain how polarity of bonds and molecular geometry affects the polarity of molecules.

What I Know

Choose the letter of the best answer. Write the chosen letter on a separate sheet of paper.

1. It refers to the ability of an atom in a molecule to attract shared electrons. a. Electron affinity b. Electronegativity c. Ionization energy d. Electromotive force

2. Which of the following statements is TRUE about polar bonds? a. They are present in metals. b. They are responsible for the formation of ionic compounds. c. They always result to the formation of polar molecular compounds. d. They may result to nonpolar covalent compounds depending on molecular geometry.

3. What type of chemical bond holds the atoms of water molecule together? a. Hydrogen bond b. Ionic bond c. Polar covalent bond d. Nonpolar covalent bond

4. Which of the following molecule is nonpolar? a. NaCl b. HCl

c. CO2

d. NH3

5. What is the electronegativity difference between Carbon and Oxygen? a. 0 b. 0.5 c. 1.0 d. 1.5

6. Supposedly a hypothetical molecule has an electronegativity difference of 0.5, what is the type of chemical bond present? a. Ionic b. Hydrogen c. Polar covalent d. Nonpolar covalent

7. What is the molecular shape of BeF3? a. Linear b. Trigonal c. Tetrahedral d. Trigonal bipyramidal

8. A molecule with a polar bond is always polar. Molecules consists of polar bonds can be nonpolar. a. Statement 1 is false, while statement 2 is true. b. Statement 1 is true, while statement 2 is false. c. Both statements are true. d. Both statements are false.

9. Which of the following pairs of atoms are bound by a polar covalent bond? a. Cl-Cl b. Mg-O c. N-H d. C-S

10. The shape of the molecule is a three-dimensional arrangement of atoms or bonding groups around a central atom. The molecular shape is governed by the valence shell electron repulsion (VSEPR) theory. a. The first and second statements are true. b. The first and second statements are false. c. The first statement is true while the second statement is false. d. The first statement is false while the second statement is true.

True or False: Write TRUE if the statement is correct, otherwise write FALSE.

11. The electronegativity of elements in the periodic table generally increases as you move from top to bottom of a group. 12. Fluorine has the highest electronegativity value while cesium and francium have the least electronegativity values. 13. Water, with a bent molecular shape, is classified as a polar molecule.

14. Sulfur hexafluoride (SF6) has six bonded electrons and no lone pair in its central atom. 15. Hydrogen cyanide (HCN) exhibits a linear geometry.

Lesson 1 Polarity of Molecules

It is interesting to have a quick glance at the lessons you have learned about compounds and chemical bonds when you were in Grades 8, 9 and 10. Can you still recall them? If you still do, then that is great!

In Grade 8, you learned that atoms combine to form molecules or compounds to attain a stable configuration that satisfies the Octet Rule. On the other hand, you have learned about chemical bonds or intramolecular forces and its three types namely ionic, covalent and metallic and the writing of Lewis dot symbol in Grade 9. In your Grade-10 Science, you have learned the concepts of electronegativity and you were briefly introduced to the topic of polarity of molecules as determined by electronegativity values.

Studying this module will certainly increase your understanding about the polarity of molecules. This module is packed with interesting activities which will make you enjoy your Chemistry lessons even more. So, are you ready to delve on an exciting quest for chemistry learning? You may start now by doing the activity below. Goodluck and happy learning!

What’s In

Chemical bonds are formed when atoms lose, accept or share electrons. An ionic bond occurs when there is a transfer of one or more valence electrons form one atom to another. It exists between metal and nonmetal atoms where metal loses electron/s while nonmetal accepts the electron/s donated by the metal. On the other hand, when two nonmetal atoms combine, neither of them loses or gains electron Instead, electron pairs are being shared by both atoms and the type of chemical bond formed is called covalent bond.

Notes to the Teacher Periodic Table is an indispensable tool in studying chemistry. In order for the learners to answer the above activity, they must first be familiar on how to use all the information written on the periodic table. At this point, they should be able to effectively use the periodic table in order to classify elements as to metal, nonmetal or semi-metals.

Tell whether the compound below is an ionic compound (IC) or covalent compound (CC) based on the type of chemical bond present.

____1. NaCl _____6. N2O

____2. CO2 ______7. PCl5

____3. CaCl2 _____8.KBr

____4. CCl4 _____9. HCl

____5. Fe2O3 _____10.AlCl3

ANSWER: NaCl, CaCl2, Fe2O3,KBr, and AlCl3 are all ionic compound because the atoms involved are combination of metal and nonmetal. On the other hand, CO2,

CCl4, N2O, PCl5 and HCl are covalent compounds because the atoms involved are both nonmetals.

It’s good that you were able to recall the difference between ionic bond and covalent bond.

You have learned that a covalent is a shared pair of electrons between two atoms. But are the electrons equally shared by the combing atoms? How does a polar covalent bond differ from a nonpolar covalent? Did you know that electronegativity of an atom can be used to further classify covalent bond into polar and nonpolar?

As you perform the activity below, you will find out that substances have different polarities, and this explains why there are substances that do not mix while others do.

What’s New

Activity1: Polarity Experiment

Materials: • Water • Vinegar • Oil • Alcohol •6 disposable glasses •a spoon Procedure: 1. Obtain 6 clean disposable glasses and prepare the following set-up. Set-up 1: 1 cup water + 5 tablespoons vinegar Set-up 2: 1 cup water + 5 tablespoons oil Set-up 3: 1 cup water + 5 tablespoons alcohol Set-up 4: 1 cup vinegar + 5 tablespoons oil Set-up 5: 1 cup vinegar + 5 tablespoons alcohol Set-up 6: 5 tablespoon oil + 5 tablespoons alcohol

2. Thoroughly stir each mixture and observe carefully. Note: •Do not forget to wash and dry the spoon after each use. • Properly label each set-up. • Samples with oil should first be mixed with dishwashing liquid before disposing down the sink

Guide Question: a. Which of the following set-ups mixed well? Which did not? b. What can you infer from the result of this activity?

In addition to what you did in the activity, answer the table that follows: Calculate the electronegativity difference and give the type of bond that exists between the atoms in each of the following pairs.

EN of the first EN of the 2nd Molecule ∆ EN atom atom 1. NaCl 2. NH3 3. CH4 4. H2 5. H2O

What is It

The polarity of molecules is determined by the two factors: the polarity of bonds based on the electronegativity difference of the atoms involved and the geometrical shape of the molecules which can be predicted via valence shell electron pair repulsion (VSEPR) theory. A. Polarity of Bonds and Electronegativity In your grade 9 chemistry, you have tackled the lesson about periodic properties of elements such as atomic size, metallic property, ionization energy, electron affinity and electronegativity. Can you still recall the definition of electronegativity? If not, no problem because it will be defined for you.

Electronegativity (EN) measures the relative tendency of an atom to attract electrons to itself when chemically combined with other atom. Take a look at the electronegativity values of some elements on Fig.1. What have you noticed? The electronegativity increases from left to right of a period and decreases from top to bottom of a group. Take note also that the higher the value of EN, the element tends to attract electron towards itself.

So what is the connection of electronegativity to the polarity of bonds? We could use the electronegativity values of the atoms involved to get the absolute electronegativity difference (∆EN) which will help us in predicting what type of chemical bond (ionic, polar covalent or nonpolar covalent) would exist between them. Table 1 shows the type of bond based on the electronegativity difference of bonded atoms.

Figure 1. Pauling Electronegativity values of some elements

Table 1. Type of bond based on electronegativity difference (∆EN) of bonded atoms

Electronegativity Type of Bond Difference (∆EN) Ionic ≥1.7 Polar Covalent 0.5 to 1.6 Nonpolar Covalent ≤ 0.4

For example, you are asked to predict what type of bond is present between the following pairs of atoms by determining their electronegativity difference.

1. Ca and Cl 2. Cl and Cl 3. H and Cl 4. S and O 5. C and N Solution:

1. ENCa = 1.0 (∆EN) = 1.0 – 3.0 = │-2.0│= 2.0 ionic bond

ENCl = 3.0

2. ENCl = 3.0 (∆EN) = 3.0 – 3.0 = 0 nonpolar covalent bond

ENCl = 3.0

3. ENH = 2.1 (∆EN) = 2.1 – 3.0 = │-0.9│= 0.9 polar covalent bond

ENCl= 3.0

4. ENS= 2.5 (∆EN) = 2.5 – 3.5 = │-1.0│= 1.0 polar covalent bond

ENO = 3.5

5. ENC= 2.5 (∆EN) = 2.5 – 3.0 = │-0.5│= 0.5 polar covalent bond

ENN = 3.0

Using the above examples, let us know more about polar and nonpolar covalent bonds. A polar covalent bond is formed when electrons are shared unequally by two atoms in a compound. The bonded pair of atoms form an electric dipole (represented by ). Dipole means “two poles” which means that a molecule has one positive end and one negative end. In this type of bond, the atom with the higher EN value becomes the partial negative pole (symbolized as ẟ-) while the atom with the lower EN value becomes the partially positive (symbolized as ẟ+) pole. Always bear in mind that the direction of the arrow is always pointing from a more electropositive pole to the more electronegative pole. Take HCl for example, H has higher EN than Cl, thus the direction of the arrow is pointing away from H and towards Cl. There is unequal electron density as represented by a size of the circle (refer to figure 2). On the other hand, a nonpolar covalent bond develops if both atoms equally share a pair of electrons between them.

This occurs when the bonding atoms have approximately equal EN value or equal ability to attract electrons to each side. Nonpolar covalent bond is an example of bond formed when two chlorine atoms combine.

(a) (b)

Figure 2. (a) Polar bond between H and Cl and (b) nonpolar bond between two Cl atoms

B. Polarity of Molecules and Molecular Geometry You just have learned how to predict the type of bond polarity simply by calculating the electronegativity difference of atoms (specifically two atoms). The next question is, how about for those molecules consisting of more than two atoms like H2O, CCl4,

NH3 and CO2? For polyatomic molecules, both the bond polarity and molecular shape determine the overall molecular polarity. In terms of molecular geometry, the valence shell electron pair repulsion (VSEPR) theory would help us to determine the spatial arrangement of atoms in a polyatomic molecule. You can predict the shape or molecular geometry of a substance using the following steps: Step 1: Determine the central atom of a molecule. The central atom is the least electronegative element.

Step 2: Draw the appropriate Lewis dot structure for the molecule. Step 3: Count the number of bonding pairs of electrons and non-bonding (or lone pairs) around the central atom. Step 4: Determine the electron pair orientation using the total number of electron pairs. Step 5: Identify the shape of the molecule of based on the location of the atoms.

Figure 3. Different Molecular Shapes

Consider the examples below:

Example 1: Predict the molecular geometry of BCl3

Step 1: ENB = 2.0 ENCl= 3.0 therefore, B will be the central atom and three Cl atoms are attached to it. By looking at the chemical formula, you will also have an idea that boron will be the central atom and three atoms of choline are attached to it. Step 2:

Step 3: The central atom has three electron pairs: 3 bonded pairs and no lone pair Step 4: The electron pair orientation for three electrons is trigonal planar.

Step 5: The molecular shape of BCl3 is trigonal planar.

Example 2: Predict the molecular geometry of CO2

Step 1: ENC= 2.5 ENO= 3.0 therefore, C will be the central atom and two O atoms will be the attached to it. (Use may also use the chemical formula to predict which atom will be the central atom

Step 2:

Step 3: For the purpose of determining the position of the bonding pairs, let

us count the double bonds as one bonding pair. Therefore, CO2 has two bonding pairs of electron. Step 4: The electron pair orientation for two electron pairs is linear.

Step 5: The molecular shape of CO2 is linear.

Example 3: Predict the molecular geometry of CHCl3.

Step 1: ENC = 2.5, ENH= 2.1 and ENCl= 3.0. Because carbon is less electronegative than chlorine and hydrogen is normally terminal atom, C must be the central atom.

Step 2:

Step 3: There are four bonding electron pairs. Step 4: The electron pair orientation for four electron pairs is tetrahedral.

Step 5: The molecular shape of CHCl3 is linear.

Now that you have learned how to determine the molecular geometry, let us now go on to our discussion of polarity of molecules based on molecular shapes. You may study the diagram below and we will use it as our guide.

NO Is the shape YES symmetrical

in 3D?

The molecule Are all atoms NO bonded to the is POLAR central atoms the same?

YES Note: You must think about a molecule in 3-D according to VSEPR Theory The molecule is NONPOLAR

Figure 4. Flowchart to determine if a molecule is polar or nonpolar Going back to our previous examples, let us try to determine the polarity of molecules of BCl3, CO2 and CHCl3.

For both BCl3 and CO2, the atoms are symmetrically arranged (trigonal planar and linear) and the attached atoms to the central atom are also the same. You must also take note that in a symmetrical molecule, the sum of the bond dipole is equal to zero (because they cancel out) and leads to the formation of nonpolar molecule. Therefore, both BCl3 and CO2 are nonpolar. On the other hand, CHCl3, although it has a symmetrical arrangement (tetrahedral), the atoms attached to the central atom are not all the same (3 chlorine atoms and 1 hydrogen atom). This causes CHCl3 to become a polar molecule. Now, let us see if you fully understood our discussion. I want you to try answering the exercises below.

Identify which molecule is polar and which is nonpolar given the Lewis structure and molecular shapes of the following molecules.

Molecule Lewis Structure Molecular Geometry Molecular (based on VSEPR) Shape

Trigonal 1. NH3 pyramidal

2. H O 2 Bent or angular

3. CCl 4 Tetrahedral

4. Linear

If you were able to answer that NH3 and H2O are polar molecules because the bond dipole cannot be cancelled because of the presence of lone pairs on the central atom and CCl4 and HBr are nonpolar molecules, you are correct. Job well done! You may now proceed to the rest of this module.

What’s More

Lewis ∆ Bond Molecular Polarity of Molecule Structure EN Polarity Geometry Molecule

1. PCl5

2. BeCl2

3. CH4

4. OF2

5. SF6 So far, we have discussed how polarity of molecules is being determined. At this point, you will perform the activity below to find out if you fully understood our topic. If you think you need to go back to the discussion part of this module while answering this activity, please feel free to do so.

What I Have Learned

In your own words, differentiate polar and nonpolar covalent bond. 1. What is electronegativity and how can it be used in in determining the polarity of molecules? 2. Is it possible for a molecule to have a polar bond but have an overall polarity of nonpolar? 3. Differentiate bonding and non-bonding electrons.

What I Can Do

Answer the following questions below:

1. Ammonia (NH3) is polar molecule while boron trifluoride (BF3) is a nonpolar molecule. Explain the difference in the polarity of these compounds. 2. Suppose that AB3E, a hypothetical molecule, is discovered. Predict whether the molecule is polar or nonpolar by determining its molecular shape.

Note: A – corresponds to central atom, B - terminal atom E – lone pair (nonbonding electrons)

Assessment

Multiple Choice. Choose the letter of the best answer. Write the chosen letter on a separate sheet of paper. 1. The following molecules have polar covalent bonds EXCEPT?

a. NH3

b. CS2

c. BCl3 d. HBr

2. Which of the following bonds is the MOST polar? a. H-Cl b. C-Cl c. H-H d. N-F

3. What is the molecular shape of CHBr3? a. Linear b. Trigonal planar c. Trigonal bipyramidal d. Tetrahedral 4. Which of the following pairs of atoms are bound by a nonpolar covalent bond? a. Na-Cl b. Ca-O c. P-N d. C-S

5. From the given Lewis structure of NH3, how many nonbonding pair/s of electron are around the central atom? a. 0 b. 1 c. 2 d. 3 6. Which of the following statements is INCORRECT? a. Polar covalent bonds can be present in a nonpolar molecule. b. Polar covalent bond is present if the electronegativity difference between atoms is equal or less than 0.4. c. Polarity of bond and molecular geometry are the two factors that affect the polarity of molecules. d. Polar bond forms when electrons are unequally shared by two atoms in a compound. 7. What is the relative ability of a bonded atom to attract shared pair of electron? a. Electron affinity b. Electronegativity c. Ionization energy d. Metallic property

8. Which description below correctly describes polar molecules? a. Polar bonds are present. b. The polar bonds are arranged so that they do not cancel. c. Lone pairs on the central atom are arranged so that they do not cancel. d. Lone pairs on the central atom are arranged so that they can be cancelled out. 9. Which of the following molecules is tetrahedral?

a. H2O

b. SF6

c. CH4

d. BF3

10. Which of the following is NOT TRUE about CO2? a. Has an electronegativity difference of 1.0 b. Polar bond is present c. Has a linear molecular shape d. Is a polar molecule True or False: Write TRUE if the statement is correct, otherwise write FALSE. 11. S and O are bound by a polar covalent bond because their electronegativity difference value is 1.0. 12. Atoms with high electronegativity have a greater tendency to attract electrons toward themselves. 13. Polarity of molecules are determined both by polarity of bonds and molecular geometry. 14. Among C-Cl, H-Cl, C-H and Cl-Cl, only Cl-Cl is polar.

15. Methyl alcohol, CH3OH, is a nonpolar molecule.

Additional Activities

Analyze the following statements, determine if each is correct or incorrect, and briefly explain your answer. Write your responses in a separate sheet.

1. SiCl4 is a nonpolar molecule.

2. H2S has a linear molecular geometry.

3. PF5 is a polar molecule.

Answer Key

F T 15.

15.

F 14. T 14.

T T 13.

13.

10.IC T 12. F 12.

CC 9. 9.

T F 11.

11. IC 8. 8. D 10. A 10.

CC 7. 7.

C C 9.

9. CC 6. 6. C 8. A 8.

IC 5. 5. B 7. B 7.

CC 4. 4. B 6. C 6.

IC 3. 3. B 5. C 5.

CC 2. 2. D C 4. 4.

IC 1. D 3. C 3.

D D 2.

More What’s B B 1.

1. Assessment Know I What

6 SF 5. polar - non Octahedral Polar 1.7

2 OF 4. polar Bent Polar 0.5

4 CH 3. nonpolar Tetrahedral polar - Non 0.4

2 BeCl 2. nonpolar Linear Polar 0.5

bipyramidal

polar polar 0.8

5 PCl 1. Trigonal Trigonal

Molecule Geometry Polarity

EN Molecule

∆

Polarity of of Polarity Molecular Bond

bond.

of valence electrons that is not shared with another atom in a covalent covalent a in atom another with shared not is that electrons valence of

covalent bonds while lone pair (nonbonding electrons) refers to a pair pair a to refers electrons) (nonbonding pair lone while bonds covalent

ose electrons involved in the formation of of formation the in involved electrons ose th are electrons Bonding Answer: Answer:

electrons. bonding - non and bonding Differentiate 4.

theory. VSEPR of condition the satisfies geometry molecular

bond but still be classified as a nonpolar molecule as long as its its as long as molecule nonpolar a as classified be still but bond

geometry. A molecule can have a polar covalent covalent polar a have can molecule A geometry. molecular and bond

Yes. Because polarity of molecule is determined both by polarity of of polarity by both determined is molecule of polarity Because Yes. Answer:

nonpolar? of polarity

Is it possible for a molecule to have a polar bond but have an overall overall an have but bond polar a have to molecule a for possible it Is 3.

polar. is bond the 1.7, than less but 0.4

EN is beyond beyond is EN the if But . nonpolar is bond the less, or 0.4 is EN the ∆ ∆

can be used to predict whether the bond will be polar or nonpolar. If If nonpolar. or polar be will bond the whether predict to used be can

attract shared electrons toward itself. The concept of electronegativity electronegativity of concept The itself. toward electrons shared attract

Electronegativity measures the tendency of an atom in a molecule to to molecule a in atom an of tendency the measures Electronegativity Answer:

molecules? of polarity

is electronegativity and how can it be used in in determining the the determining in in used be it can how and electronegativity is What 2.

atoms. between electrons of sharing equal is

electrons between atoms, while nonpolar bonds are formed when there there when formed are bonds nonpolar while atoms, between electrons

Polar bonds are formed when there is an unequal sharing of of sharing unequal an is there when formed are bonds Polar Answer:

bond. covalent nonpolar and polar differentiate words, own your In 1.

ned Lear Have I What

nonpolar.

midal shape and therefore it is is it therefore and shape midal bipyra trigonal a exhibit will configuration

3 E E AB an with molecule a theory, VSEPR of concept the Using

electrons) (nonbonding pair lone – E

atom terminal - B

atom, central to corresponds – A Note:

shape. molecular its determining by nonpolar or polar s i molecule the

3 E, a hypothetical molecule, is discovered. Predict whether whether Predict discovered. is molecule, hypothetical a E, AB that Suppose 2.

nonpolar. it making pair, lone no has

trigonal planar geometry with three bonding pairs of electron and central atom atom central and electron of pairs bonding three with geometry planar trigonal

3 has a a has BF hand, other the On polar. it makes his t pair), pair/lone nonbonding

a trigonal pyramidal shape, with four electron pairs (3 bonding pairs and 1 1 and pairs bonding (3 pairs electron four with shape, pyramidal trigonal a

3 has has NH Since geometry. molecular its by determined is molecule of Polarity Answer: Answer:

compounds. these of polarity the in difference the Explain ecule. mol

3 3 ) is a nonpolar nonpolar a is ) (BF trifluoride boron while molecule polar is ) (NH Ammonia 1.

do can I What

nonpolar. molecule overall the making

5 ) exhibits a trigonal bipyramidal based on VSEPR theory theory VSEPR on based bipyramidal trigonal a exhibits ) (PF pentafluoride

EN is 1.9 (polar bond is present), Phosphorus Phosphorus present), is bond (polar 1.9 is EN value the Though Correct. ∆ ∆

5 5 molecule. polar a is PF 3.

pairs. lone two as h also atom central the wherein representation

2 2 2 E AB by represented is molecule The sulfur. atom, central electronegative

dipole moment. Two partially positive hydrogen atoms are attached to the more more the to attached are atoms hydrogen positive partially Two moment. dipole

2 a bent molecular geometry which gives it an upwards net net upwards an it gives which geometry molecular bent a has S H Incorrect.

2 geometry. molecular linear a has S H 2.

pair. lone have not does atom central

classified as nonpolar molecule because it has a tetrahedral geometry and the the and geometry tetrahedral a has it because molecule nonpolar as classified

4 is still still is SiCl 0.8, is EN because present is bond polar Though Correct. ∆

4 4 molecule. nonpolar a is SiCl 1.

Activities: Additional

References

Department of Education- Bureau of Secondary Education (2003). Lesson Plans in Science III(Chemistry). CHED-PNU. (2006). Teaching Guide in Senior High School-Physical Science. Commission on Higher Education. C.P. Garcia Ave., Diliman, Quezon City. Retrieved from https://lrmds.deped.gov.og/detail/14519 last May 19, 2020

Punzalan, J.M. &Monserat, R.C. (2016). Science in Today’s World for Senior High School- Physical Science. Sibs Publishing House, Inc. Quezon City, Philippines. Padua, A.L., Padolina, M.C.D., Crisostomo, R.M., &Alumaga, M.J.B. (2016). Physical Science. Vibal Group Inc. G. Araneta Avenue, Quezon City Santiago, K. S., & Silverio, A.A. (2016). Exploring Life Through Science-Physical Science. Pheonix Publishing House, Inc. Quezon Avenue, Quezon City. Religioso, T.F., & Cordero-Navaza, D. (2017). You and the Natural World- Physical Science. Phoenix Publishing House, Inc. Quezon Avenue, Quezon City.

For inquiries or feedback, please write or call:

Department of Education - Bureau of Learning Resources (DepEd-BLR)

Ground Floor, Bonifacio Bldg., DepEd Complex Meralco Avenue, Pasig City, Philippines 1600

Telefax: (632) 8634-1072; 8634-1054; 8631-4985

Email Address: [email protected] * [email protected]

Physical

Science

Physical Science Polarity of Molecules and Its Properties First Edition, 2020

Published by the Department of Education Secretary: Leonor Magtolis Briones Undersecretary: Diosdado M. San Antonio

Development Team of the Module

Writers: Bayani T. Vicencio, Valeria Amor C. Rosita Editors: Priscilla D. Domino Gertrudes L. Malabanan Reviewers: Rogelio D. Canuel, Elmer C. Bobis, Gertrudes L. Malabanan Illustrator: Geselle A. Teaňo Layout Artist: Elsie R. Reyes Management Team: Wilfredo E. Cabral, Regional Director Job S. Zape Jr., CLMD Chief Elaine T. Balaogan, Regional ADM Coordinator Helen A. Ramos, Schools Division Superintendent Rhina O. Ilagan, Assistant Schools Division Superintendent Edna U. Mendoza, CID Chief Ronaldo V. Ramilo, EPS-in-Charge, LRMS

Department of Education – RegionIV-A CALABARZON

Office Address: Gate 2 Karangalan Village, Barangay 1900, Cainta, Rizal 1800 Telefax: 02-8682-5773/8684-4914/8647-7487 E-mail Address:[email protected]/[email protected]

Physical Science Polarity of Molecules and Its Properties

Introductory Message

For the facilitator:

Welcome to the Physical Science 11/12Alternative Delivery Mode (ADM) Module on Polarity of Molecules and Its Properties!

In addition to the material in the main text, you will also see this box in the body of the module:

Notes to the Teacher This contains helpful tips or strategies that will help you in guiding the learners.

For the learner:

Welcome to the Physical Science 11/12 Alternative Delivery Mode (ADM) Module on Properties of Molecules based on its Polarity!

The hand is one of the most symbolic parts of the human body. It is often used to depict skill, action and purpose. Through our hands we may learn, create and accomplish. Hence, the hand in this learning resource signifies that you as a learner is capable and empowered to successfully achieve the relevant competencies and skills at your own pace and time. Your academic success lies in your own hands!

This module has the following parts and corresponding icons:

This will give you an idea of the skills or What I Need to Know competencies you are expected to learn in

the module.

This part includes an activity that aims to What I Know check what you already know about the

lesson to take. If you get all the answers correctly (100%), you may decide to skip this module.

This is a brief drill or review to help you link What’s In the current lesson with the previous one.

In this portion, the new lesson will be What’s New introduced to you in various ways such as a

story, a song, a poem, a problem opener, an activity or a situation.

This section provides a brief discussion of What is It the lesson. This aims to help you discover

and understand new concepts and skills.

This comprises activities for independent What’s More practice to solidify your understanding and

skills of the topic. You may check the answers to the exercises using the Answer Key at the end of the module.

This includes questions or blank What I Have Learned sentence/paragraph to be filled in to

process what you learned from the lesson.

This section provides an activity which will What I Can Do help you transfer your new knowledge or

skill into real life situations or concerns.

This is a task which aims to evaluate your Assessment level of mastery in achieving the learning

competency.

In this portion, another activity will be given Additional Activities to you to enrich your knowledge or skill of

the lesson learned. This also tends retention of learned concepts.

This contains answers to all activities in the Answer Key module.

At the end of this module you will also find:

References This is a list of all sources used in developing this module.

The following are some reminders in using this module:

We hope that through this material, you will experience meaningful learning and gain deep understanding of the relevant competencies. You can do it!

Week

What I Need to Know

This module was designed and written with you in mind. It is here to help you master the concept of polarity of molecules. The scope of this module permits it to be used in different learning situations. The language used recognizes the varied vocabulary level of students. The lessons are arranged to follow the standard sequence of the course. But the order in which you read them can be changed to correspond with the textbook you are now using.

The module is divided into three lessons, namely: ● Lesson 1 – Properties of Molecules based on its Polarity

After going through this module, you are expected to: 1. define solubility, miscibility and polarity; 2. identify the different types of intermolecular forces of attraction; 3. explain how polarity of molecules related to its properties

What I Know

Choose the letter of the best answer. Write the chosen letter on a separate sheet of paper.

1. Which of the following is TRUE of polar molecules? i. Have high boiling point iii. low surface tension ii. Have high melting point iv. High vapor pressure a. I only b. I and II only c. II and III only d. IV only

2. Which of the following intermolecular forces of attraction (IMFA) is arranged from strongest to weakest? a. H- bonding – dipole-dipole – London forces b. London-forces – dipole-dipole – H-bonding c. Dipole-dipole – London forces – H- bonding d. H-bonding – London forces – dipole-dipole

For numbers 3-6, consider the choices below: a. boiling point c. Viscosity b. solubility d. vapor pressure

3. Refers to the resistance of a liquid to flow. 4. Is temperature at which the liquid starts to boil. 5. Defined as the pressure exerted by a substance when in its gaseous state. 6. The ability of a substance to be dissolved in another substance to form a solution.

7. The following are examples of viscous substances EXCEPT: a. blood c. vinegar b. honey d. syrup

8. Which of the following is NOT TRUE about water? a. has high surface tension b. has high boiling point c. has low viscosity d. becomes denser when freezes

9. Which of the following substances will most likely be miscible in water?

a. Benzene (C6H6)

b. Ethyl alcohol (C2H6O)

c. carbon tetrachloride (CCl4)

d. toluene (C6H5CH3)

10. Which of the following will dissolve in polar solvents? a. nonpolar solvents and ionic compounds b. ionic compounds and polar covalent compounds c. nonpolar solvents and covalent compounds d. all of the above

True or False: Write T if the statement is true, otherwise write F. 11. The floating of ice on liquid water is an indication that ice has higher density than liquid water. 12. The volatility of a substance depends on its vapor pressure. 13. Alcohol is less volatile than vinegar.

14. Between water (H2O) and carbon tetrachloride (CCl4), water has higher boiling point. 15. Vapor pressure is inversely proportional to the strength of intermolecular forces present.

Lesson Properties of Molecules 1 based on its Polarity

From the previous module, you learned how to determine the polarity of bonds using the concept of electronegativity. Also, you learned that polarity of molecules is affected by both the polarity of bonds and its molecular shape or geometry.

What’s In

Let us have some warm up exercise for our nerve cells before we proceed to the presentation of our lesson. You will perform a simple activity that will help you recall some basic concepts related to polarity of molecules. Have some fun!

Notes to the Teacher There are numerous terms or concepts being studied in science and most of them are either difficult to spell out or pronounce. As teachers, we should think of engaging activities that would motivate our students to learn and at the same time increase their vocabulary skills and spelling ability. Below is an example of an activity you could employ in your class.

WORD CRYPTOGRAM

Directions: Unscramble the letters by placing the correct letter sequence in the shaded boxes to come up with the correct answer for each number. Use the numbered boxes to complete the answer to the riddle below.

L E C M O U L E

1 5 6

O P A L R O D N B

3 9

3. L E C M O U L E O N L E A P I R 1 5 6 2 14 8 16

N A R O P O L N B D O N

7 12

A C E G T R O T L I Y E I T E N V

11 15 4 10 17

M A T O

RIDDLE: It shows the three-dimensional arrangement of bonding

groups of atoms around a central atom.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

Can you define the following words/terms that you have decoded?

What’s New

Analyze the lyrics of the song, “Tubig at Langis”, and answer the questions below.

TUBIG AT LANGIS Sharon Cuneta

Tubig at langis, ang katayuannati’yyan ang kawangis Pilitinmangmagsam’y may mahahapis Ganyang-ganyantayongdalawa Ang panuntunan’ymagkaiba Langis at tubig, ‘di mapagsama ng tunaymangpag-ibig Hinanakit ang s’yanglagingmananaig Mahal na mahal man kita May mahal ka namang iba

Chorus: Tubig at langis Idarang man sainit, ‘di rin tatamis Dahil ang halo’yluha’tpaghihinagpis Ang kirot ay di maalis kung labis Bakitnanaig ang dusasaligayasa ‘ting daigdig ? May dasalbaakonghindiN’yanarinig ? Papelnatinsapag-ibig Ako’ylangis, ika’ytubig

Repeat Chorus: Bakitnanaig ang dusasaligayasa ‘ting daigdig ? May dasalbaakonghindiN’yanarinig ? Papelnatinsapag-ibig Ako’ylangis, ika’ytubig Ako’ylangis, ika’ytubig

Guide Question: 1. What is the message of the song? 2. If you add oil to the water, what will happen? Will it create a single homogenous phase or will it form two layers? Why? 3. Why do you think water and oil cannot be mixed even when heated? Support your answer.

What is It

A. Polarity, Solubility, and Miscibility One of the practical applications of polarity of molecule in real-life scenario is manifested on the solubility and miscibility of substances to form solution.

Solubility is defined as the ability of a solid substance to be dissolved in a given amount of solvent while miscibility is the ability of the two liquids to combine or mix in all proportions, creating a homogenous mixture.

The general rule to remember about the solubility and miscibility of molecular compounds can be summarized in a phrase, “like dissolves like” or “like mixes with like”. This means that polar substances will only be dissolved or mixed with polar substances while nonpolar substances will be soluble or miscible with another nonpolar substance.

Try the exercises below in order to assess how much you have understood the solubility (and miscibility) rule of substances in relation to their polarity.

Which of the following substances below will most likely mix with each other?

a. water (H2O) and chloroform (CHCl3)

b. benzene (C6H6) and chloroform (CHCl3)

c. water (H2O) and vinegar (CH3COOH)

d. acetone (C3H6O) and toluene (C6H5CH3)

e. carbon tetrachloride (CCl4) and water (H2O)

What chemistry concept did you used in answering the question above? If you answered polarity of molecules, then you are on the right track. Great job! Benzene and chloroform are both nonpolar compounds while water and vinegar are both polar compounds, thus they are miscible to each other. However, the rest is a combination of polar and nonpolar molecules and therefore will not mix and instead will form two layers even if shaken or carefully stirred.

B. Bond Strength and Physical Properties of Covalent Compounds

From the previous module, you learned the intramolecular forces of attraction, the attractive force that binds atoms together. In this module, you will learn another type of attractive force, the intermolecular forces of attraction (IMFA) which exists between molecules.

In this lesson, we will not discuss IMFA in so much detail because it will be tackled next module. We will just focus on the following salient features of IMFA and its effect on the physical properties of covalent compounds:

1. There are several types of IMFA and below they are arranged from STRONGEST to WEAKEST. Ion-dipole → H-bonding→ dipole-dipole→dipole-induced dipole→ London forces of attraction 2. The strength of IMFA greatly affects the physical properties of substances such as boiling point, melting point, vapor pressure, surface tension, etc.

Before we move further, try to perform the exercise below to test your ability to analyze concepts and principles that you have learned from the discussion.

Put a check (/) to those properties applicable for polar molecule.

____1. High boiling point ____7. High vapor pressure ____2. Low boiling point ____8. Low vapor pressure ____3. High melting point ____9. High surface tension ____4. Low melting point ____10. Low surface tension ____5. High volatility ____11. H-bonding & dipole-dipole present ____6. Low volatility ____12. London dispersion is present

How well did you perform in this exercise? Continue reading for you to find out the correct answers for this activity.

From the above discussion you learned that there are several types of IMFA and their relative strength as compared to other types. Strong intermolecular forces tend to yield solids and liquids while weak intermolecular forces favor formation of gases.

Table 1 shows the comparison of the various types of IMFA while table 2 shows the physical properties of polar and nonpolar molecules as affected by the type of IMFA present.

Table 1. Summary of Types of Intermolecular Forces of Attraction (IMFA)

Type of IMFA Interacting Substances Examples Ion-dipole Ion (cation or anion) and a NaCl dissolved in H2O; 2 polar molecule Ca + and PCl3 Hydrogen bonding Polar molecules H2O, NH3, CH3OH containing H chemically bonded to a small and highly electronegative nonmetal atom such as N, O, and F Dipole –dipole Polar molecules CH3F and H2S; HCl; Dipole-induced dipole Polar and nonpolar HI and CH4 molecules

London forces All substances and solely O2, N2, He gas, Br2 for nonpolar molecules and noble gases Table 2. General Properties of polar and nonpolar molecules

Polar molecules Nonpolar molecules • IMFA type: H-bonding • IMFA type: London and dipole-dipole dispersion • exist as solids or liquids • exist as gases at room at room temperature temperature • High boiling point • Low boiling point • High melting point • Low melting point • High surface tension • Low surface tension • Low vapor pressure • High vapor pressure • Low volatility • High volatility • Soluble in water • Insoluble in water

Let us define the physical properties of substances:

A. Boiling point: temperature at which the vapor pressure and atmospheric pressure of a liquid substance are equal.

B. Melting point: temperature at which solid becomes liquid. At this point, the solid and liquid phases exist in equilibrium.

C. Surface tension: energy needed to increase the surface area by a unit amount;

D. Viscosity: the resistance of the liquid to flow

E. Vapor pressure: pressure exerted by a substance in its gaseous state.

F. Volatility: measures the rate at which a substance vaporizes (changes from liquid to gas)

In the simplest sense, boiling point, melting point, viscosity and surface tension increase as the strength of intermolecular forces increases. On the other hand, vapor pressure and volatility decrease with increasing strength of IMFA. London dispersion forces increase as the molecular mass of a substance increases.

What’s More

Activity 1. Strength of IMFA and Physical Properties of Covalent Compounds

For each pair of molecules, identify the one with the higher boiling point (BP), melting point (MP), viscosity (V), surface tension (ST) and vapor pressure (VP). Briefly explain your choice.

BP MP V ST VP

Methane, CH4 carbon tetrachloride, CCl4

Dihydrogen sulfide, H2S water, H2O

Methanol, CH3OH ethanol, CH3CH2OH

Acetic acid, CH3COOH acetone, CH3OCH3 Adapted from Punzalan and Monserat (2016)

What I Have Learned

1. Distinguish intramolecular forces of attraction and intermolecular forces of attraction.

2. In your own words, explain the Solubility Rule for polar and non polar substances.

3. Compare and contrast polar and non-polar molecules based on their physical properties.

4. What relationship can you derive between the strength of IMFA and the physical properties of covalent molecules?

What I Can Do

A. Using the concept of bond polarity and solubility, explain why water (H2O) and vinegar are miscible, but vinegar and oil are immiscible.

B. Using the concept of intermolecular forces of attraction, explain why butter melts at room temperature but solidifies when refrigerated.

C. Explain the importance polarity of molecules to biological processes such as in the structure of proteins and phospholipids.

Assessment

Multiple Choice: Choose the letter of the best answer. Write the chosen letter on a separate sheet of paper.

1. Which of the following IMFAs is considered as the weakest? a. H-bonding b. Ion-dipole c. Dipole-dipole d. London forces

2. The boiling point of water is greater than dihydrogen sulfide because of ______. a. Dipole-dipole bond b. H-bonding c. London dispersion d. Ion-dipole

3. Which of the following substances will dissolve most likely in water? a. Oil

b. Carbon tetrachloride (CCl4)

c. Vinegar (CH3COOH)

d. Hexane (C6H14)

4. Which of the following molecules has high melting point?

a. CHCl3

b. CCl4

c. BCl3

d. BeCl2

5. ______refers to the energy required to increase the surface area by a unit amount. a. Viscosity b. Surface tension c. Vapor pressure d. Density

6. Which of the following statements is TRUE about nonpolar molecules? a. high boiling point b. high melting point c. low surface tension d. low vapor pressure

7. Which of the following substances is miscible in hexane (C6H14)?

a. Acetone (C3H6O)

b. Vinegar (CH3COOH)

c. Chloroform (CHCl3)

d. Methanol (CH3OH)

8. The following are intermolecular forces of attraction EXCEPT: a. H-bond b. Dipole-dipole c. Covalent bond d. London forces

9. Which of the following properties has indirect relationship with the strength of IMFA? a. Boiling point b. Melting point c. Surface tension d. Vapor pressure

10. In which of the following solvents would molecular iodine (I2) be most soluble? a. Vinegar b. Water c. Ethyl alcohol d. Carbon tetrachloride

True or False: Write T if the statement is true, otherwise write F. 11. H-bonds are broken when ice melts. 12. Molecules with H-bonds have higher boiling point than molecules with dipole- dipole bond. 13. In covalent molecules, vapor pressure decreases with decreasing strength of intermolecular forces. 14. When the attractive forces holding particles together are greater, you have to get to a higher temperature to break those forces, so the melting point is higher. 15. The strength of dispersion (London) forces tends to increase with increased molecular weight.

Additional Activities

1. Briefly explain why water is oftentimes called the “universal solvent”. 2. Using the concept of IMFA, account for the difference in boiling point and melting point of the following molecular substances:

Substance Boiling point (0C) Melting point (0C)

Helium gas, He -269 -272

Methane, CH4 -162 -184

H2O 100 0

Ethanol, C2H5OH 78 -117

Answer Key

F 15. F 15.

T 14. T

14. F 13. F 13.

T 12. T

12.

F 11. F 11.

D 10. B

10.

D 9. B 9.

C 8. D 8.

C 7. C

7. C 6. B 6.

B 5. D

A 4. A 4.

C 3. C

CRYPTOGRAM B 2. A 2.

D 1. WORD WORD C 1.

ent Assessm More What's

Know I What

17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2

Y R T E M O E G R A L U C E L O M

RIDDLE

M O T

A 6.

17 10 4 15 11

Y T I V I T A G E N O R T C E L E

12 7

D N O B R A L O P N O N

16 8 14 2

R I A P E N O L

9 3

D N O B R A L O P

6 5

E L U C E L O M

More What's

3 3 3 OCH CH acetone, COOH CH acid, Acetic

acid acid

cetic cetic a than mass molar

lower has acetone however

bonding bonding - H have Both

3 3 OCH CH

COOH CH

3 2 3 3 OH CH CH ethanol, OH CH Methanol,

ethanol

molar mass than than mass molar

lower has methanol but

bonding bonding - H have Both

3 OH CH

OH CH CH 2 3

2 2 O H water, S

H sulfide, Dihydrogen

dipole

- dipole than stronger is which

2 S H binding binding -

H is type IMFA and

Because it is polar molecule molecule polar is it Because

2 O

H 4 Methane, CH Methane, 4 ride, CCl ride, tetrachlo carbon

forces London

dipole which is stronger than than stronger is which dipole

4 CH

- dipole is type IMFA and

molecule polar is it Because

CCl

VP ST V MP BP

More What’s

metallic bonds constitute the intramolecular forces intramolecular the constitute bonds metallic

within between a molecule. Ionic, covalent and and covalent Ionic, molecule. a atoms exist forces

solutes are only soluble (miscible) to nonpolar solvents. Intramolecular Intramolecular solvents. nonpolar to (miscible) soluble only are solutes while nonpolar nonpolar while oa slts r slbe msil) ny o oa solvents polar to only (miscible) soluble are solutes polar

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Rule. Solubility the explain , words own your In 2.

attraction. of forces intermolecular of examples are forces

dipole and London London and dipole - dipole bond, - H dipole, - Ion molecules. between attraction

attraction. On the other hand, intermolecular forces of attraction are forces of of forces are attraction of forces intermolecular hand, other the On attraction.

ramolecular forces of of forces ramolecular int the constitute bonds metallic and covalent

Intramolecular forces of attraction exist within a molecule. Ionic, Ionic, molecule. a within exist attraction of forces Intramolecular Answer:

attraction. Distinguish intramolecular forces of attraction and intermolecular forces of of forces intermolecular and attraction of forces intramolecular Distinguish

Learned have I What

is inversely proportional to the strength of IMFA. of strength the to proportional inversely is

portional to the strength of IMFA while VP VP while IMFA of strength the to portional pro directly are ST and

increases with decreasing strength of IMFA. Therefore, BP, MP, V V MP, BP, Therefore, IMFA. of strength decreasing with increases increase with increasing strength of IMFA. Vapor pressure pressure Vapor IMFA. of strength increasing with increase

Boiling point, melting point, viscosity and surface tension tension surface and viscosity point, melting point, Boiling

Answer:

hysical properties of covalent molecules? covalent of properties hysical p the and

What relationship can you derive between the strength of IMFA IMFA of strength the between derive you can relationship What

water in Insoluble •

water in Soluble •

volatility High • volatility Low •

pressure vapor High •

pressure vapor Low •

tension surface Low • tension surface High •

point melting Low •

point melting High •

point boiling Low • point boiling High •

temperature temperature room at

room at gases as exist • liquids or solids as exist •

dipole - dipole and

dispersion

London type: IMFA • bonding - H type: IMFA •

molecules ar Nonpol

molecules Polar

Answer:

properties. physical

polar molecules based on its its on based molecules polar - non and polar contrast and Compare

Learned have I What

solid. becomes butter thus acids fatty between assembled

nside the freezer, the temperature decreases and more London forces gets gets forces London more and decreases temperature the freezer, the nside i

rotate and move freely. On the other hand, when you placed the butter butter the placed you when hand, other the On freely. move and rotate

increases, more London forces are disrupted and fats begin to vibrate, vibrate, to begin fats and disrupted are forces London more increases,

London forces of attraction between fatty acids. As the amount of heat heat of amount the As acids. fatty between attraction of forces London

of melting requires heat that disrupts the the disrupts that heat requires melting of change physical The forces.

together by a weak attractive van der Waals interaction called London London called interaction Waals der van attractive weak a by together

Butter is composed of complex mixture of fatty acids held held acids fatty of mixture complex of composed is Butter Possible answer: answer: Possible

refrigerated. when solidifies but temperature room at melts

n, explain why butter butter why explain n, attractio of forces intermolecular of concept the Using B.

mix. not will they therefore substance, nonpolar a is oil

while polar is vinegar hand, other the On other. each to miscible are they

Water and vinegar are both polar substances therefore therefore substances polar both are vinegar and Water le answer: le Possib

immiscible. are oil and vinegar but miscible, are vinegar and

2 O) O) (H water why explain solubility, and polarity bond of concept the Using A.

What I Can Do Can I What

effectively. membrane

membrane can perform its function of being selectively permeable permeable selectively being of function its perform can membrane er while its hydrophobic part is oriented inward. In this way, the cell cell the way, this In inward. oriented is part hydrophobic its while er

wat it forms a micelle wherein its hydrophilic part has a close contact with with contact close a has part hydrophilic its wherein micelle a forms it

fearing) end. When placed in water, water, in placed When end. fearing) - (water hydrophobic and end loving)

(water hydrophilic a has It membrane. cell the in present are hand,

it can no longer perform its basic function. Phospholipids, on the other other the on Phospholipids, function. basic its perform longer no can it

polar and nonpolar groups. Once its shape has been altered or modified, modified, or altered been has shape its Once groups. nonpolar and polar

ected by attraction and repulsion among its its among repulsion and attraction by ected aff is proteins of shape The

a long chain and it also has the ability to bend to form various shapes. shapes. various form to bend to ability the has also it and chain long a nonpolar ends which are essential for life processes to occur. It can form form can It occur. to processes life for essential are which ends nonpolar

Proteins are macromolecules having polar and and polar having macromolecules are Proteins

answer: Possible

phospholipids. d

an proteins of structure the in as such processes Explain the importance polarity of molecules to biological biological to molecules of polarity importance the Explain

Do Can I What

100

References

101

For inquiries or feedback, please write or call:

Department of Education - Bureau of Learning Resources (DepEd-BLR)

Ground Floor, Bonifacio Bldg., DepEd Complex Meralco Avenue, Pasig City, Philippines 1600

Telefax: (632) 8634-1072; 8634-1054; 8631-4985

Email Address: [email protected] * [email protected]

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Physical

Science

103

Physical Science General Types of Intermolecular Forces First Edition, 2020

Published by the Department of Education Secretary: Leonor Magtolis Briones Undersecretary: Diosdado M. San Antonio

Development Team of the Module

Writers: Valeria Amor C. Rosita, Bayani T. Vicencio Editors: Priscilla D. Domino, Gertrudes L. Malabanan Reviewers: Rogelio D. Canuel, Elmer C. Bobis, Gertrudes L. Malabanan Illustrator: Geselle A. Teaño Layout Artist: Elsie R. Reyes Management Team: Wilfredo E. Cabral, Regional Director Job S. Zape Jr., CLMD Chief Elaine T. Balaogan, Regional ADM Coordinator Helen A. Ramos, Schools Division Superintendent Rhina O. Ilagan, Assistant Schools Division Superintendent Edna U. Mendoza, CID Chief Ronaldo V. Ramilo, EPS-in-Charge, LRMS Management Team: Wilfredo E. Cabral, Regional Director

Department of Education – Region IV - A CALABARZON Job S. Zape Jr., CLMD Chief

Office Address: Gate Elaine 2 Karangalan T. Balaogan V,illage, RegionalBarangay ADM CoordinatorSan Isidro Cainta, Rizal 1800 Susan DL. Oribiana, Schools Division Telefax:Superintendent 02-8682-5773/8684-4914/8647-7487 E-mail Address: [email protected] V. Maranan, /[email protected] Schools Division Superintendent

Lorna R. Medrano, CID Chief Edita T. Olan, EPS-in-Charge, LRMS Editha M. Malihan

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Physical Science General Types of Intermolecular Forces

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Introductory Message

For the facilitator:

Welcome to the Physical Science 11/12 Alternative Delivery Mode (ADM) Module on General Types of Intermolecular Forces!

In addition to the material in the main text, you will also see this box in the body of the module:

Notes to the Teacher This contains helpful tips or strategies that will help you in guiding the learners.

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For the learner:

Welcome to the Physical Science 11/12 Alternative Delivery Mode (ADM) Module on General Types of Intermolecular Forces !

The hand is one of the most symbolic parts of the human body. It is often used to depict skill, action and purpose. Through our hands we may learn, create and accomplish. Hence, the hand in this learning resource signifies that as a learner, you are capable and empowered to learn by yourself. Relevant competencies and skills can be successfully achieved at your own pace and time. Your academic success lies in your own hands!

This module has the following parts and corresponding icons:

What I Need to Know This will give you an idea of the skills or

competencies you are expected to learn in the module.

What I Know This part includes an activity that aims to

check what you already know about the lesson to take. If you get all the answers correctly (100%), you may decide to skip this module.

What’s In This is a brief drill or review to help you link

the current lesson with the previous one.

What’s New In this portion, the new lesson will be

introduced to you in various ways such as a story, a song, a poem, a problem opener, an activity or a situation.

What is It This section provides a brief discussion of

the lesson. This aims to help you discover and understand new concepts and skills.

What’s More This comprises activities for independent

practice to solidify your understanding and skills of the topic. You may check the answers to the exercises using the Answer Key at the end of the module.

What I Have Learned This includes questions or blank

sentence/paragraph to be filled in to process what you learned from the lesson.

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What I Can Do This section provides an activity which will

help you apply your new knowledge or skill into real life situations or concerns.

Assessment This is a task which aims to evaluate your

level of mastery in achieving the learning competency.

Additional Activities In this portion, another activity will be given

to you to enrich your knowledge or skill of the lesson learned. This also tends retention of learned concepts.

Answer Key This contains answers to all activities in the

module.

At the end of this module you will also find:

References This is a list of all sources used in developing this module.

The following are some reminders in using this module:

We hope that through this material, you will experience meaningful learning and gain deep understanding of the relevant competencies. You can do it!

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Week

What I Need to Know

This module was designed and written with you in mind. It is here to help you master the General Types of Intermolecular Forces. The scope of this module permits it to be used in different learning situations. The language used recognizes the varied vocabulary level of students. The lessons are arranged to follow the standard sequence of the course. But the order in which you read them can be changed to correspond with the textbook you are now using.

The module is divided into two lessons, namely:  Lesson 1 – How the general types of intermolecular forces are described  Lesson 2 – Intermolecular forces present between and among substances

After going through this module, you are expected to: 1. describe the types of intermolecular forces present in substances, and 2. identify the types of intermolecular forces present between and among substances.

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What I Know

Choose the letter of the best answer. Write the chosen letter on a separate sheet of paper.

1. Forces that are present between and among molecules a. ionic b. covalent c. intermolecular d. intramolecular

2. Forces that are present between an ion and a polar molecule a. ion-dipole b. dipole-dipole c. dispersion forces d. hydrogen bonding

3. The ease with which the electron distribution in the atom or molecule can be distorted a. diffusion b. polarizability c. dipole moment d. induced dipole

4. Attractive forces that arise as a result of temporary dipoles induced in atoms or molecules a. dipole forces b. induced dipole c. dispersion forces d. instantaneous dipole

5. An interaction between the H-atom in a polar bond and an electronegative atom such as O, N, or F a. H-bonding b. dipole-dipole c. London forces d. ion-induced dipole

6. The strongest among the intermolecular forces of attraction. a. ion-dipole b. H-bonding c. dipole-dipole d. dipole-induced dipole

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7. Attractive forces between polar molecules where the positive end of one molecule aligns to the negative end of another molecule a. ion-dipole b. dipole-dipole c. dispersion forces d. ion-induced dipole

8. It results when an ion or polar molecule is placed near an atom or a nonpolar molecule such that the electron distribution is distorted by the force exerted by the said substances a. H-bonding b. ion-dipole forces c. dispersion forces d. dipole-dipole interaction

9. The strength of London dispersion forces is a function of the molar mass of a substance. As the molar mass increases the strength of interaction between molecules due to dispersion forces a. increase b. decrease c. remain the same d. cannot be measured

10. A heat of hydration is the result of favourable interaction between the cations and anions of an ionic compound with water. The nature of this attraction is a. H-bonding b. ion-dipole forces c. dispersion forces d. dipole-dipole interaction

11. The measure of the shift of the electron density towards the atom with a higher electronegativity value a. Polarity b. Polarizability c. Dipole moment d. Forces of interaction

12. The strength of ion-dipole interaction depends on the ions present. with ions of the same magnitude, which is true about this interaction? a. Cations interact more strongly that anions because their charges are less concentrated. b. Cations interact more strongly that anions because their charges are more concentrated. c. Anions interact more strongly that anions because their charges are less concentrated. d. Anions interact more strongly that anions because their charges are more concentrated.

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13. At any point of time the shift in the position of the electrons in an atom will likely create a temporary positive and negative poles known as: a. dipole forces b. dipole moment c. dispersion forces d. instantaneous dipole

14. The force/s of attraction present between the species I and NO- 2 3 a. London dispersion forces b. H-bonding and ion-induced dipole interaction c. Van der Waals interaction and dipole-dipole interaction d. London dispersion forces and ion-induced dipole interaction

15. Which the following substances contain molecules that are capable of forming hydrogen bond among themselves? a. ethane (C2H6) b. acetic acid (CH3COOH) c. beryllium hydride (BeH2) d. potassium fluoride (KF)

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Lesson Types of Intermolecular 1 Forces

Atoms in molecules and ionic substances are attracted to each other either by sharing or complete transfer of electrons. These attractive forces keep the molecules intact.

But, how do molecules or substances stay together and exhibit properties that are unique to them? This is known as bulk properties.

In this lesson, you will learn how the different forces of attraction known as intermolecular forces keep substances together. You will also be able to identify the intermolecular forces present between and among substances, thus their bulk properties can be predicted.

What’s In

This simple activity will help you recall what you understood about Lewis electron dot structure and polarity of molecules. The polarity of substances will guide you in identifying the intermolecular forces present between and among molecules.

Notes to the Teacher 1. This module will help the students understand the concepts of intermolecular forces (IMF). 2. Allow the students to answer each part thoroughly, either individually or in pairs. 3. Let the students check the answers to each part. Have a short discussion of the concepts involved after checking. 4. The students will then move to the next part of the module. They will have the feedback and discussion after every part. 5. Inputs can be given in addition to the discussion in this module. 6. Kindly entertain questions for further discussions.

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Directions: 1. Use a clean sheet of paper to answer this part.

2. Copy the table and fill up with the correct information.

3. Show the direction of the dipole moment for each molecule.

Substance LEDS Shape Polarity

1. CCl2F2

2. N2

3. CH 4

4. H O 2

5. CO

Polarity of molecules based on the LEDS

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What’s New

Activity 1:

Using the illustrations below, describe the attractions between substances by completing each sentence with the correct words. Tell what kind of attractive forces keep the substances together. 1.

This attraction happens between polar molecules. The charges align so that the ______pole of one molecule is attracted to the ______end of the other molecule. This kind is called of interaction ______.

The ______sodium ion is attracted to the partially ______end of water molecules. this attraction is referred to as ______.

A ______ion or ______approaches a neutral nonpolar substance. This results to a distortion of the substance and leads to the development of positive and negative poles. This attraction is called ______.

A permanent ______approaches a neutral nonpolar substance resulting to a ______dipole. This form attraction is considered as ______.

The partially- ______oxygen of one water molecule is ______to the partially- ______hydrogen of the other water molecule. This is called a/an ______.

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Activity 2: Identify the intermolecular forces present among the following species.

a. Two Sulfur dioxide (SO2) molecules

+ b. Sodium ion (Na ) and formaldehyde (CH2O)

c. Two Carbon dioxide (CO2) molecules

d. Ammonia (NH3and H2O)

2+ e. Fe and O2

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What is It

This section provides a brief and thorough discussion of the concepts of intermolecular forces. The different types of intermolecular forces are described to be congruent with the first objective of this module. The second discussion is about the strategies to identify the intermolecular forces present between and among molecules. Activity 1:

Atoms are held together in molecules by strong intramolecular forces, like covalent and ionic bonds. On the other hand, other forms of attractive forces are present to keep these molecules together giving rise to the different states of matter, which, then exhibit their own bulk properties such as boiling, melting, and freezing points, and viscosity among others.

There are three general types of intermolecular forces (IMF), namely, van der Waals forces, ion-dipole interaction, and H-bonding.

Van der Waals forces, after the Dutch chemist Johannes van der Waals (1837-1923) consist of dipole-dipole interaction, dipole-induced dipole interaction, and dispersion forces. Dipole-dipole attraction is present among polar molecules. Through constant movement, the charges of the molecules align in such a way that the positive (+) end of one molecule is attracted to the negative (-) end of the other molecule. This happens due to the shift of electron density towards the more electronegative element in the molecule resulting to (+) and (-) ends. The measure of this electron shift is known as dipole moment, represented by crossed arrow, .

Dipole-induced dipole interaction, just like the dipole-dipole forces, depends on the presence of polar molecules. The other molecule needs not be a polar one. The partial charges present in the dipole cause the polarization or distortion of the electron distribution in the other molecule. This gives rise to regions of partial (+) and (-) poles. The other molecule then becomes an induced dipole. The induced dipole will be attracted to the original polar molecules, resulting to dipole-induced dipole attraction.

Dispersion forces (London dispersion forces), were named after the German physicist Fritz London (1900-1954). The electron cloud of a neutral substance can be normally distributed around the nucleus. At any given time, the electron distribution may be uneven and results to an instantaneous dipole. This temporary dipole will then influence the neighboring atoms through attractive and repulsive forces. Eventually, the substances will become instantaneous dipoles, too. Attraction between opposite charges will happen among the species present. These are true for ion-induced dipole and induced dipole-induced dipole interactions.

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Ion-dipole interaction results from the attraction either between a cation (+) or an anion (-) with permanent polar molecules. The ions will be attracted to the opposite charges present in the dipole resulting to this type of attraction.

H-bonding is a special type of dipole-dipole interaction between the H- atoms in a polar bond. It requires that the H-atoms in the molecules be bonded with more electronegative atoms such as O, N, or F to form H-bonds with other molecules.

All interacting substances exhibit the presence of London dispersion forces in addition to other forces of attraction among them.

Activity 2: Intermolecular forces (IMF) present among species

Polar substances exhibit dipole-dipole interaction due to the presence of (+) and (-) ends of the molecules. In the exercise above, sulfur dioxide (SO2) has polar ends that will participate in the dipole-dipole forces of attraction.

With the presence of an ion (cation or anion), the charged ends of polar molecules will be attracted to the dipole. This is true in the case of Na+ and formaldehyde. The positive sodium ion will be attracted to the partially-negative oxygen in formaldehyde, resulting to an ion-dipole interaction.

For the third example, CO2 is a nonpolar substance. It is a linear molecule and the electron shift at the right of C is balanced by the electron shift to the left. Thus there is no net shift in electron density and no net charged is produced. For nonpolar molecules, only dispersion forces are present.

In both NH3 and H2O, the hydrogen atoms are bonded to more electronegative atoms, nitrogen and oxygen, respectively. This permits them to form H-bonds with other molecules with the same condition. Thus, H-bond is present between NH3 and H2O.

Ion-induced dipole forces of attraction are present among Fe2+ ions together with oxygen molecules. The charge in iron will distort the electron 2+ distribution in O2 resulting to temporary poles in oxygen. The Fe and partially- negative end of O2 will then be attracted to form the above-mentioned force of attraction. In all of the examples above, London dispersion forces are also present.

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What’s More

Activity 1.1 Description of Intermolecular Forces

Match Column A with column B. Choose the letters of the correct answer and write it on your answer sheet. Column A Column B 1. Attractive forces between polar molecule a. hydration 2. Electrostatic attraction between an ion b. ion-induced dipole and a polar molecule 3. Favorable interaction between the ions c. H-bonding of an ionic compound and water 4. Distortion of the electron distribution d. polarizability of an atom or molecule brought about e. dipole-dipole by an ion or a polar molecule 5. Dispersion of charges when an ion f. dipole-induced dipole approaches a molecule 6. Happens when a H-atom bonded to g. ion-dipole electronegative atoms, such as O, N, F approaches a nearby electronegative atom 7. Dispersion of charges when a dipole h. dipole approaches a nonpolar molecule i. cations 8. The ease with which electron distribution j. dispersion forces is distorted k. anions 9. Substance with positive and negative ends 10. Positively-charged ions

Activity 2.1 Intermolecular Forces present among species

Identify the intermolecular forces present in the following species.

1. Chlorine gas (Cl2)

2. Carbon monoxide (CO)

3. Sulfur dioxide (SO2)

4. Dichloromethane (CH2Cl2)

5. Dimethyl ether (CH3-O-CH3)

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What Have I Learned

1. What are the general types of intermolecular forces?

2. Describe the following in your own words. a. van der Waals forces a.1 dipole-dipole interaction a.2 dipole-induced dipole interaction a.3 dispersion forces b. ion-dipole interaction

c. H-bonding

3. List down the intermolecular forces present in each species. a. HBr

b. CS2

c. C2H6

d. CH3COOH

e. Br2

What I Can Do

Knowledge of concepts is not enough for a learning experience to be meaningful. We should also understand how the concepts we learned on intermolecular forces can be applied to real life situation to get the most out of what we learned. Let us look at this simple situation that will help us realize the advantage of fully understanding intermolecular concepts. Situation: Storage of different substances at home needs careful attention. Alcohol, acetone, and hair sprays, even gasoline should be taken care of to avoid fire. Where should these substances be stored? Why do we need extra precaution in keeping them at home? Relate your answer to intermolecular forces.

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Assessment

Choose the letter of the best answer. Write the chosen letter on a separate sheet of paper.

1. What is True about intermolecular forces? a. They are strong bonds that form between atoms of molecules. b. Substances can form more than one but one will predominate. c. They are stronger than the intramolecular forces between atoms. d. There is a vague relationship between intermolecular forces and bulk properties.

2. Ion-dipole interaction results from the a. Attraction between an ion and a polar molecule. b. Repulsion between a dipole and another dipole. c. Repulsion between a polar with a nonpolar molecule. d. Attraction between a polar with another polar molecule.

3. Why is the strength of interaction due to dispersion forces increases as the number of electrons increase? a. The electron distribution of big molecules is easily polarized. b. The nucleus in the molecules has greater effective shielding effect. c. The electrons move freely around the nucleus resulting to greater energy. d. The electrons in the molecules can easily jump from one orbital to another.

4. Which of the following sets of interactions are all van der Waals forces? a. ion-induced dipole; dipole-dipole; London dispersion forces b. dipole-dipole; dipole-induced dipole; London dispersion forces c. London dispersion forces; ion-induced dipole; dipole-induced dipole d. dipole-induced dipole; ion-induced dipole; London dispersion forces

5. London dispersion forces are formed when:

a. there is instantaneous dipole that influences neighboring substances to gain dipoles. b. there is permanent (-) and (+) ends that participate in electrostatic attractions. c. the electron cloud of the atoms is evenly distributed around the nucleus. d. the atoms of two neighboring molecules participate in give and take of electrons.

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6. How does dipole-dipole interaction form? a. Polar molecules shift electron density that gives rise to neutral substances. b. The electron distribution in the polar molecules is distorted that results to (-) and (+) poles. c. Polarization of big nonpolar molecules causes the formation of permanent (+) and (-) charges. d. The (-) and (+) ends of one polar molecule align themselves to the (+)and (-) ends of another polar molecule and attract each other.

7. During ion-dipole interactions, the cation causes the a. repulsion of charges among the molecules. b. distortion of the electron distribution in the dipole. c. attraction of the (-) ion to the (+) end of a permanent dipole. d. formation of (+) ions that are attracted to the permanent dipole.

8. H-bonding forms when the substances involved are polar and there are ______. a. H-atoms of a molecule interact with to O, N, F of other molecules. b. C-atoms attached to O, N, F. c. central atoms with O, N, F as attached atoms. d. unshared pair of electrons in the central atom.

9. Which ions will result to higher ion-dipole interactions? a. anions b. divalent c. cations d. monatomic

What intermolecular forces are present between the molecules of the following substances?

10) CH4

11) CH3COOH

12) O3

13) N2

14) NH3

15) PCl5

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Additional Activities

This part will test whether you fully understood what intermolecular forces are present between and among molecules. You can answer this by recalling the strategies discussed earlier in this module. Remember also that there may be more than one IMF present in the among molecules of the given substances.

Identify the intermolecular forces present in the following substances.

1) Silicon tetrafluoride, SiF4

2) Acetone, CH2O

3) Methyl alcohol, CH3OH

4) Methane, CH4

5) Phosphorus trichloride, PCl3

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Answer Key

dispersion London

15. bonding - H

dipole; - dipole forces;

London dispersion dispersion London

14.

forces

B 15.

London dispersion dispersion London 13.

D 14.

dipole - dipole forces;

13.

dispersion London 12. I

10.

B 12.

bonding - H

dipole - dipole H 9. C 11.

dipole; dipole; -

dipole forces;

LDF, 5. D 8. D 10.

London dispersion dispersion London 11.

dipole - dipole F 7. A 9.

forces

4.LDF, C 6. C

ion ion Dispers London 10.

dipole - dipole B 5. B

7. C 9.

LDF, 3. J 4. A 6.

dipole - dipole A 3. A 5.

2.LDF, G 2. D 4.

D 6.

LDF 1. E 1. B 3.

A 5.

B 4.

Act 2.1 Act. 1.1 .

C 1.

A 3.

More What's Know I What

Assessment

What’s In

Polarity of molecules based on the LEDS

Substance LEDS Shape Polarity

1. CCl2F2 (Freon-12) Tetrahedral Polar

2. N2 (Nitrogen gas) Linear Nonpolar

3. CH4 (Methane) Tetrahedral Nonpolar

4. H2O (Water) Nonpolar Bent

5. CO (Carbon Linear monoxide) Polar

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What’s New

dipole induced - ion forces, dispersion London 5.

bonding - H dipole, - dipole forces, dispersion London 4.

forces dispersion London 3.

dipole - ion forces, dispersion London

dipole - dipole forces, dispersion London

2 Act.

ing bond - H interaction: of Kind ; positive attracted, negative, 5.

dipole induced - dipole interaction: of Kind temporary; dipole, 4.

dipole induced - ion intersection; of Kind ; cation positive, 3.

dipole - ion : interaction of Kind ; negative positive, 2.

dipole - dipole n: interactio of Kind ; positive negative, partially

Act.1

What Have I Learned

forces dispersion London e.

forces dispersion London

bonding - H interaction, dipole - dipole forces, dispersion London

c. forces dispersion London b.

dipole - dipole forces, dispersion London a. 2.

molecules. the of polarization or distribution

electron the of distortion the from result forces Dispersion a3)

dipoles. temporary to resulting

distribution electron the of larization po the causes that dipole

a of presence the on depends interaction dipole induced - Dipole a2)

molecules. the of poles ) - ( the

to attracted be will (+) the that so themselves align that charges

) - ( and (+) of presence the on s depend intraction dipole - Dipole a1)

molecules.

be either repulsive or attractive depending on the distance of the the of distance the on depending attractive or repulsive either be

2a) van der Waals forces are interactions between molecules that can can that molecules between interactions are forces Waals der van 2a)

bonding. - H and interaction, dipole - ion

rces are van der Waals forces, forces, Waals der van are rces fo intermolecular of types general The

Additional Activities

interaction dipole - dipole , forces dispersion London 5.

forces dispersion London

interaction dipole - le dipo bonding, - H , forces dispersion London 3.

interaction dipole - dipole , forces dispersion London

forces dispersion London

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References

Shawn P.Shields. “Analyzing Strengths of Intermolecular Forces.” Accessed May 25, 2020. https://www.youtube.com/watch?v=kU5nRCB4jJ8 BCcampus. “Intermolecular Forces.” Accessed May 21, 2020. https://opentextbc.ca/chemistry/chapter/10-1-intermolecular-forces/ Chang, Raymond.2005. Chemistry (8th. Ed.).New York, NY: McGraw-Hill Education (Asia). Chegg Study. “Textbook Solutions.” Accessed May 23, 2020. https://www.chegg.com/homework- help/explain-glycerol-viscous-water- acetone-less-viscous-water-gl-chapter-7-problem-99p- solution- 9780077274290-exc chemlibretexts. “Liquids and Intermolecular Forces (Summary).” Accessed May 21, 2020. https://chem.libretexts.org/Bookshelves/General_Chemistry/Map%3A_Chemistry_ - _The_Central_Science_(Brown_et_al.)/11%3A_Liquids_and_Intermolecular_F orces/11.S%3A _ Liquids_and_Intermolecular_Forces_(Summary) chemlibretexts. “Properties of Matter.” Accessed May 25, 2020. https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemist ry_Textbook_M aps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Physical _Properties_of_ Matter chemlibretexts. “Solubility and Intermolecular Forces.” Accessed May 21, 2020. https://www.google.com/search?q=solubility+and+intermolecular+forces&o q=solubility+and+intermolecular&aqs=chrome.0.0j69i57j0l4.13287j0j8&sour ceid=chrome&ie=UTF-8 Clutch. “Formal Charges of Ozone.” Accessed May 25, 2020. https://www.clutchprep.com/chemistry/practice-problems/131828/what- are-the-formal-charges-in-o3-ozone Clutch. “Lewis Structure of HF.” Accessed May 25, 2020. https://www.clutchprep.com/chemistry/practice-problems/110784/look- at-the-lewis- structure-for-hf-where-are-the-nonbonding-electrons

Clutch. “Molecular Geometry of CH3NH2.” Accessed May 25, 2020. https://www.clutchprep.com/chemistry/practice-problems/108201/what- is-the-molecular- geometry-about-nitrogen-in-ch3nh2 Elmhurst College. “Intermolecular Forces.” Accessed May 20, 2020. http://chemistry.elmhurst.edu/vchembook/160Aintermolec.html

Liberal dictionary. “Pentane.” Accessed May 23, 2020. https://www.liberaldictionary.com/pentane/

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Nutrients Review.com. “Glycerin (Glycerol).” Accessed May 22, 2020. http://www.nutrientsreview.com/carbs/edible- glycerin.html Quora. “What is the formula and structure of water?” Accessed May 24, 2020. https://www.quora.com/What-is-the-formula-structure-of-water Study.com. “Ether: Preparations and Reactions.” Accessed May 20, 2020. https://study.com/academy/lesson/ether-preparation-reactions.html

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Physical Science

129

Physical Science Effects of Intermolecular Forces on Properties of Substances First Edition, 2020

Published by the Department of Education Secretary: Leonor Magtolis Briones Undersecretary: Diosdado M. San Antonio

Development Team of the Module

Department of Education – Region IV-A CALABARZON

Office Address: Gate 2 Karangalan Village, Barangay San Isidro Cainta, Rizal 1800 Telefax: 02-8682-5773/8684-4914/8647-7487 E-mail Address: [email protected]/[email protected]

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Physical Science Effects of Intermolecular Forces on Properties of Substances

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Introductory Message

For the facilitator:

Welcome to the Physical Science 11/12 Alternative Delivery Mode (ADM) Module on Effects of Intermolecular Forces on Properties of Substances!

In addition to the material in the main text, you will also see this box in the body of the module:

Notes to the Teacher This contains helpful tips or strategies that will help you in guiding the learners.

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For the learner:

Welcome to the Physical Science 11/12 Alternative Delivery Mode (ADM) Module on Effects of Intermolecular Forces on Properties of Substances!

The hand is one of the most symbolic parts of the human body. It is often used to depict skill, action and purpose. Through our hands we may learn, create and accomplish. Hence, the hand in this learning resource signifies that as a learner, you are capable and empowered to learn by yourself. Relevant competencies and skills can be successfully achieved at your own pace and time. Your academic success lies in your own hands!

This module has the following parts and corresponding icons:

What I Need to Know This will give you an idea of the skills or

competencies you are expected to learn in the module.

What I Know This part includes an activity that aims to

check what you already know about the lesson to take. If you get all the answers correctly (100%), you may decide to skip this module.

What’s In This is a brief drill or review to help you link

the current lesson with the previous one.

What’s New In this portion, the new lesson will be

introduced to you in various ways such as a story, a song, a poem, a problem opener, an activity or a situation.

What is It This section provides a brief discussion of

the lesson. This aims to help you discover and understand new concepts and skills.

What’s More This comprises activities for independent

practice to solidify your understanding and skills of the topic. You may check the answers to the exercises using the Answer Key at the end of the module.

What I Have Learned This includes questions or blank

sentence/paragraph to be filled in to process what you learned from the lesson.

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What I Can Do This section provides an activity which will

help you transfer your new knowledge or skill into real life situations or concerns.

Assessment This is a task which aims to evaluate your

level of mastery in achieving the learning competency.

Additional Activities In this portion, another activity will be given

to you to enrich your knowledge or skill of the lesson learned. This also tends retention of learned concepts.

Answer Key This contains answers to all activities in the

module.

At the end of this module you will also find:

References This is a list of all sources used in developing this module.

The following are some reminders in using this module:

We hope that through this material, you will experience meaningful learning and gain deep understanding of the relevant competencies. You can do it!

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Week

What I Need to Know

This module was designed and written with you in mind. It is here to help you master the Effects of Intermolecular Forces on the Properties of Substances. The scope of this module permits it to be used in different learning situations. The language used recognizes the varied vocabulary levels of students. The lessons are arranged to follow the standard sequence of the course. But the order in which you read them can be changed to correspond with the textbook you are now using.

After going through this module, you are expected to:

1. identify the intermolecular forces present in each of the given substances.

2. compare the strengths of intermolecular forces in pairs of substances.

3. predict which among the given substances will exhibit higher boiling, melting,

and freezing points, viscosity, surface tension, and solubilities.

4. explain the effects of intermolecular forces on the properties of substances.

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What I Know

Choose the letter of the best answer. Write the chosen letter on a separate sheet of paper.

1. Liquids can form spherical elastic film to minimize surface area. What intermolecular force is responsible for the formation of this film in water? a. H-bonding b. ion-induced dipole c. dipole-induced dipole d. London dispersion force

2. The amount of energy required to stretch or increase the surface of a liquid by a unit area a. specific heat b. surface tension c. vapor pressure d. heat of vaporization

3. The ability of water molecules to move against gravity a. viscosity b. temperature c. surface tension d. capillary action

4. Substances like heavy syrup and molasses flow slowly than water. The ability of these substances to resist flow is known as a. viscosity b. pressure c. surface tension d. capillary action

5. The pressure exerted by the vapor due to evaporation of a liquid or a solid in a closed container a. boiling point b. capillary action c. surface tension d. vapor pressure

6. What is true about liquids with strong intermolecular forces? a. Vapor pressure is low. b. Vapor pressure is high. c. Viscosity tends to be low. d. Viscosity is immeasurable.

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7. Which of the following occurs when the vapor pressure of a liquid becomes equal to the atmospheric pressure? a. boiling b. melting c. freezing d. condensing

8. Using the chart on the vapor pressure of the four substances, which among them has the lowest boiling point?

Vapor Pressure @ Substance 250C, atm Diethyl ether (C2H5)2O 0.7 Bromine (Br2) 0.3 Ethyl alcohol (C2H5OH) 0.08 Water (H2O) 0.03

a. water b. bromine c. ethyl alcohol d. diethyl ether

9. Based on the LEDS below, which has a lower boiling point and what accounts for the difference based on the intermolecular forces present in each species?

Diethyl ether Ethyl alcohol

a. Ethyl alcohol has a lower boiling point due to the dispersion forces present among the molecules. b. Ethyl alcohol has a higher boiling point because of the predominant H-bonding present among the molecules. c. Diethyl ether has a lower boiling point due to dipole-dipole interaction. d. Diethyl ether has a higher boiling point because it is capable of forming H-bond.

10. The atmospheric pressure on top of a mountain is lower than at sea level. As a consequence, what will happen to the cooking time of an egg on top of the mountain? a. The egg will cook faster since the boiling temperature will be lower. b. The egg will cook at a shorter time since the boiling temperature will be higher. c. The egg will cook at a longer time due to a lower boiling temperature. d. The egg will cook at a shorter time due to higher boiling temperature.

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11. Sodium chloride is completely soluble in water. What is responsible for its solubility in water? a. London dispersion forces in NaCl predominate leading to strong dipole interactions with water. b. The presence of charged ends in NaCl enables dipole-dipole interaction with water. c. The ions in NaCl participate in ion-induced dipole attractions with water. d. Na+ and Cl- ions are favorable sites for H-bonding to form.

12. Xenon has a higher atomic mass than neon. Xe has 131.3 amu while Ne has 20.2 amu. The boiling points are 166.1K and 27.3K, respectively. How do intermolecular forces account for the difference? a. Dipole- dipole interaction is greater in Xe than Ne so more energy is needed to break the bonds. b. H-bonding is greater for substances with higher atomic mass so greater energy is needed to change Xe to vapor. c. Atomic weight increases the chance of lesser dispersion forces so greater energy is needed to separate Xe atoms to change to vapor d. London dispersion forces is greater in substances with heavier atomic mass so greater energy is needed to separate the atoms of Xe than Ne.

13. Which is more viscous between glycerol and water based on their LEDS and intermolecular forces?

Glycerol Water a. Glycerol because it has more OH- groups that form London dispersion forces among the molecules. b. Glycerol because it has more OH- groups that form H-bonding among the molecules. c. Glycerol because it has less OH- groups that form London dispersion forces among the molecules. d. Glycerol because it has less OH- groups that form H-bonding forces among the molecules.

14. When does boiling occur? a. When the vapor pressure of a liquid is equal to atmospheric pressure. b. When evaporation occurs at the same time with condensation. c. When the rate of vaporization is equal to the rate of condensation. d. When the amount of vapor inside the container is equal to the amount of the liquid.

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15. Which is true of vapor pressure? a. It is affected by the surface area of the liquid or solid. b. Vapor pressure is higher when the temperature of the molecule is low. c. Molecules with high molar heat of vaporization has low vapor pressure. d. When vapor pressure is lower than atmospheric pressure, boiling occurs.

Lesson Effects of Intermolecular Forces on the Properties of 1 Substances

The properties of matter can be seen from either the sub-microscopic or macroscopic level. The sub-microscopic level includes the atoms, molecules, and ions which we cannot see. The macroscopic level shows how the bulk properties are exhibited by matter. These properties include surface tension, viscosity, boiling, melting, and freezing points, and solubility. Intermolecular forces play a very important role to determine how substances behave at the macroscopic level.

In this lesson, you will learn how the different forces of attraction bring about the bulk properties exhibited by substances. This lesson will help you understand why a certain substance behaves differently from others.

What’s In

This simple activity will help you recall what you understood about the types of intermolecular forces present in each substance.

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Notes to the Teacher 1. This module will help the students remember the concepts of intermolecular forces (IMF) and the forces of attraction present among species. 2. Allow the students to answer each part thoroughly, either individually or in pairs. 3. Let the students check the answers to each part. Have a short discussion of the concepts involved after checking. 4. The students will then move to the next part of the module. They will have the feedback and discussion after every part. 5. Inputs can be given in addition to the discussion in this module. 6. Kindly entertain questions for further discussions.

Directions: 1. Use a clean sheet of paper to answer this part.

2. Copy the table and fill it up with the correct information.

3. Show the direction of the dipole moment for each molecule.

Intermolecular Forces Present in Substances

Intermolecular Substance LEDS Shape Polarity Forces Present

1) CH3OH

2) O3

3) CH3NH2

4) I2

5) HF

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What’s New

Activity 1:

Factors affecting the strength of intermolecular forces among molecules Refer to the pairs of substances to answer the questions that follow.

a. NaCl (sodium chloride) and CH4 (methane) b. CCl4 (carbon tetrachloride) and CHCl3 (trichloromethane or chloroform) c. NH3 (ammonia) and CH3F (methyl fluoride) d. PCL5 (phosphorus pentachloride) and PBr5 (phosphorus pentabromide) e. C5H12 (pentane) and C5H12 (isopentane) f. F2 (Fluorine) and Br2 (Bromine)

1. Identify the intermolecular forces present in the substances in each pair. 2. Which of the forces predominates in each substance? 3. Choose which substabce will have greater intermolecular forces of attraction. 4. Predict which substance in each pair will have higher boiling and melting points.

Activity 2:

1. Refer to the chart below on physical properties of matter. Answer the questions and relate the intermolecular forces present among the species to explain the different properties exhibited by the substances.

Melting and Boiling Points Molar Mass, Boiling Substance Melting Point, K g/mol Point, K

Fluorine (F2) 38 53 85

Bromine (Br2) 160 266 332

Astatine (At2) 420 575 610

a. Which substance has the highest melting and boiling points? b. What intermolecular forces of interactions are present in each of the substances? c. How do the intermolecular forces present relate to the size of the substance? d. How do the strength of the intermolecular forces present in each species compare to each other? e. How does the strength of the intermolecular forces relate to the boiling and melting points of the substances?

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What is It

This section gives brief and thorough explanation on how intermolecular forces affect the bulk properties of matter, namely surface tension, viscosity, boiling, melting, and freezing points, and solubility.

Activity 1:

The properties of substances as viewed on the macroscopic level can be explained by the types of intermolecular forces present between and among substances. These bulk properties can be predicted through an analysis of the interplay of intermolecular forces in each substance.

The chart below tells us of the relative strengths of intermolecular forces. This can be used as reference when the IMF is being related to the properties of substances.

Relative Strengths of Intermolecular Forces

Ion-dipole Strongest

H-bonding

Dipole-dipole

Dipole-induced dipole

London dispersion forces Weakest

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Properties of substances affected by intermolecular forces

 Surface Tension

This is the amount of energy required to stretch the surface area of liquids (e.g., 1 cm2). Liquids with high intermolecular forces tend to have high surface tensions. When water is dropped on a waxy surface, it tends to form a round bead to minimize the surface area that it occupies.

An example of surface tension is capillary action. It is the ability of liquid molecules to move against gravity. The forces bringing about capillary action are cohesion (intermolecular attraction between like molecules) and adhesion (an attraction between unlike molecules.

Water molecules exhibit cohesion while the attraction between water and the sides of the glass tube is adhesion. If adhesion is stronger than cohesion, the liquid is pulled upward.

If cohesion is greater than adhesion, there is a depression or lowering, resulting to a lower height of the liquid in the capillary tube.

The stronger the intermolecular forces possessed by molecules, the higher is the surface tension of the substance.

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 Viscosity

This is a measure of a liquid’s resistance to flow. The greater the viscosity of a liquid, the more slowly it flows. The viscosity of substances decreases with high temperatures; thus, syrup flows faster when hot. The strength of intermolecular forces affects the ease with which substances flow. Liquids that have high intermolecular forces are highly viscous. Also, the presence of strong H-bonds in some liquids makes these substances highly viscous. The LEDS of glycerol below shows three (3) OH- groups that can participate in H-bonding whereas water has only one OH- group to form H- bonding. Glycerol is more viscous than water.

Glycerol

Water

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 Boiling Point and Melting Point

Boiling point depends on the equilibrium vapor pressure exerted by the liquid or solid above the liquid or the solid. This means that the rate of vaporization is equal to the rate of condensation of the substance in a closed container. Vapor pressure also varies with temperature. The graph below shows the effect of temperature on the vapor pressure of water.

Source: https://www.chem.purdue.edu/gchelp/liquids/vpress.html

At 100OC, the vapor pressure is equal to the atmospheric pressure of 1.00 atm. Boiling occurs at this point, where the vapor pressure of water is equal to the pressure of the atmosphere. There are substances that boil at a lower temperature and some at a higher temperature. These temperatures depend on the vapor pressure exerted by the liquids or solids. Vapor pressure, on the other hand, depends on the intermolecular forces present in the substances. When the intermolecular forces are strong, the vapor pressure is low. As a consequence, boiling will occur at a higher temperature because more energy is needed to break the intermolecular bonds for the substance to change into vapor. Water, for example, exhibits strong H-bonds such that vaporization needs more energy to change the liquid to vapor.

London dispersion forces predominate in methane, CH4. These are the weakest forces of attraction among molecules. It needs a little energy to break the bonds such that methane changes to vapor easily. As a consequence, more vapor are released in which vapor pressure will eventually equal to atmospheric pressure. Boiling then will occur. This explains why water has a higher boiling point than methane.

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This condition is also true for melting point. The ease with which bond breaks affects the melting points of substances. The greater intermolecular forces there are among molecules, the higher is their melting point. The strength of dispersion forces also depends on the size of the molecules of the substance or the number of electrons in the molecules of the substance. The ease with which the electron distribution is distorted explains the amount of dispersion forces that a substance exhibits. The distortion of the electron distribution is known as polarizability. The greater the polarizability of the electron distribution the greater are the dispersion forces. When the dispersion forces are high, the boiling and melting points are also high.

Br2 and F2 are both diatomic gases. They are also both nonpolar, but Br2 is a bigger molecule than F2. The polarizability of Br2 is greater than F2 so it has greater dispersion forces. This explains why Br2 has a higher boiling point than F2. Greater amount of energy is needed to overcome the big dispersion forces in Br2 than in F2.

 Solubility

Solubility is the ability of a substance (solid, liquid, or gas) to dissolve in a given substance (solid, liquid, or gas). The amount of any substance dissolved in a solvent (the substance that dissolves another substance) depends on the types of interaction among molecules, pressure, and temperature.

The rule “like dissolves like” applies to solubility. This means that the kind of substances being dissolved should exhibit the same properties or should be compatible for them to form solutions. The polarity of molecules is an important factor for substances to dissolve in certain molecules. Highly polar molecules will dissolve substances that have dipoles. The negatively-charged particles will be attracted to the positively-charged particles of the involved substances. This attraction will subsist in the solutions.

Water is often considered as a universal solvent because of its ability to dissolve almost numerous substances. Remember that water is incapable of dissolving all solutes (especially non polar substances), but water has the ability to form H-bonds with polar substances, and polar substances abound in nature.

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Nonpolar substances, on the other hand will also dissolve nonpolar substances. Intermolecular forces, such as dispersion forces, will prevail to maintain the dissolution of substances.

To predict the behaviour of substances, several considerations should be taken.

First, the polarity of substances should be determined together with the predominant intermolecular forces present in the substances. For example, consider NaCl (sodium chloride) and CH4 (methane). NaCl is a dipole while methane is nonpolar. Dipole-dipole interaction is predominant in NaCl while dispersion forces are present among methane molecules. Since dipole-dipole forces are stronger than dispersion forces, NaCl will have higher boiling and melting points. It is also highly soluble in water due to ion- dipole interaction that will prevail. Mwthane is not soluble in water because there are no poles that will participate in the dissolution process with water.

Between CCl4 (carbon tetrachloride) and CHCl3 (trichloromethane), trichloromethane has a higher boiling and melting points than carbon tetrachloride. It is also slightly soluble in water. Trichloromethane is a polar molecule while carbon tetrachloride is a nonpolar molecule. The dipole-dipole interaction in CHCl3 is stronger than the dispersion forces in CCl4. Again the boiling and melting points are higher in CHCl3 than in CCl4. Hence, since CHCl3 is polar, then it is soluble in water.

Ammonia (NH3) and methyl fluoride (CH3F) are both polar but the ability of NH3 to form H-bonds qualifies it for higher boiling and melting points than CH3F. At the same time, H-bonding also enables NH3 to be more soluble in water than CH3F.

Phosphorus pentachloride (PCL5) and phosphorus pentabromide (PBr5) have the same molecular shape and polarity. What matters here is the size of the molecule when comparing the properties of these substances. Bromine contains more electrons than chlorine. This makes PBr5 bigger and heavier. In this case, dispersion forces are greater in PBr5 so it has higher boiling and melting points than PCL5. Since these two substances are both nonpolar, then they are not soluble in water.

Pentane (C5H12) and isopentane (C5H12) both contain the same number of C and H atoms in the formula. However, their molecular structures are different. Below are the LEDS of the two substances.

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Pentane has an extended structure while isopentane has a compact structure. Extended structures provide more opportunities for interactions than compact structures. Extended molecules have stronger intermolecular forces than the compact structures. As such the boiling point of pentane is higher than that of isopentane. It is also true for their melting points. Both molecules are nonpolar so they are not soluble in water.

Pentane

Isopentane

The nature of intermolecular forces present in molecules is a good gauge to predict properties of substances.

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What’s More

Activity 1.1

1. Identify the principal type of solute-solvent interaction responsible for forming the following solutions:

a. KNO3 in H2O

b. Br2 in benzene (C6H6)

c. HCl in acetonitrile (CH3CN)

d. HF in H2O

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2. Which pair/s of substances will dissolve in each other? a. CH3NH2 and H2O b. CH3-CH3 and CH3OH c. SO2 and CH4 d. MgCl2 and H2O e. CH2 = CH2 and CH4

3. Arrange the following substances in the order of increasing boiling points.

a. Ethanol b. Ethane

c. Ethylene glycol d. Methane

e. Methanol

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What Have I Learned

1. What are the properties of matter influenced by intermolecular forces? 2. Rank the intermolecular forces in the order of increasing strengths. 3. What steps or considerations do we take to determine the effects of intermolecular forces on the properties of matter?

What I Can Do

Situation: You are asked by your mother to cook pork nilaga. You have only an ordinary kettle to use for cooking. She even reminds you to save energy because we are in a state of pandemic due to covid-19. Saving resources nowadays is a must because we are not sure of the world’s economy. As a student of Physical Science and with your knowledge of properties of matter in relation to intermolecular forces, how are you going to perform your task in such a way that energy is not wasted?

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Assessment

Choose the letter of the best answer. Write the chosen letter on a separate sheet of paper. 1. The properties of matter seen in the macroscopic level influenced by intermolecular forces a. bulk b. ionic c. covalent d. individual

2. Which intermolecular forces depend on the polarizability of molecules a. ion-dipole b. dipole-dipole c. Hydrogen bonding d. London dispersion forces

3. Cohesive forces bring about capillary action. These forces are a. pulling molecules towards gravity. b. interactions among polar molecules. c. attractions among different molecules. d. drawing together of the same kind of molecules.

4. When adhesion is stronger than cohesion, the liquid is pulled a. upward and results to concave meniscus. b. downward and results to convex meniscus. c. upward and becomes higher than the surrounding liquid. d. downward and becomes higher than the surrounding liquid.

5. What is TRUE about viscosity of substances? a. Viscosity of substances increases as the temperature increases. b. The least viscous substance flow the slowest among the substances. c. Molecules that form H-bonds have higher viscosities than those with London dispersion forces. d. Substances with London dispersion forces exhibit greater viscosity than those with ion-dipole interactions.

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6. When intermolecular forces are high, the boiling point is expected to be a. low. b. high. c. dependent on the kind of atoms. d. dependent on the number of atoms.

7. Water is a polar molecule that is capable of forming H-bonds. What is expected of its vapor pressure? a. It will be low since weak intermolecular forces are present. b. The polar ends will hinder the breaking of bonds, thus less water vapor is produced. c. Vapor pressure will be high since great amount of energy is needed to break the H-bond. d. Vapor pressure will be low since it is hard to break the H-bond among the molecules and escape as vapor.

8. Which intermolecular forces among the following allows for easy escape of molecule to the vapor phase?

a. H-bonding b. ion-dipole forces c. dipole-dipole interaction d. London dispersion forces

9. The vapor pressure on top of the mountain is low so what will happen to the cooking time of an egg up there?

a. The cooking time will be longer since the temperature of the water is higher. b. The cooking time will be shorter since the temperature of the water is higher. c. The cooking time will be longer since the temperature of the water is lower. d. The cooking time will be shorter since the temperature of the water is lower.

10. Naturally, methane will not dissolve in water because a. greater molar mass of H2O than CH4. b. the same intermolecular forces they possess. c. difference in the kinds of atoms in their structure. d. difference in intermolecular forces between the two substances.

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11. Which among the following substances has lower viscosity than methyl alcohol?

a. Water, H2O b. Ethylene glycol

c. acetone d. ethyl alcohol

12. Arrange the following substances in increasing boiling points.

I. CO2 II. H2O III. O2 IV. C6H12O6

a. I, II, III, IV b. III, I, II, IV c. III, II, I, IV d. II, I, IV, III

Identify the predominant intermolecular forces present between each pair of molecule.

13. Water (H2O) and acetic acid (CH3COOH)

14. Carbon dioxide (CO2) and methane (CH4)

15. Potassium iodide (KI) and Water (H2O)

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Additional Activities

This part will test whether you fully understand the influences of intermolecular forces present between and among species to the bulk properties of substances. You can answer this by recalling the strategies discussed earlier in this module. Remember also that the predominant intermolecular forces are the determinants of what the bulk properties of substances will be.

Explain the differences in boiling point in terms of intermolecular forces (IMF).

a. HF (20° C) and HCl (-85° C)

b. CHCl3 (61° C) and CHBr3 (150° C)

c. Br2 (59° C) and ICl (97° C)

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Answer Key

interaction

dipole dipole - Ion 15.

C 15. forces

London dispersion dispersion London 14. C 14.

glycol Ethylene

bonding - H 13. B 13.

< Ethanol < Methanol

B 12. D 12.

C 11. B 11.

Soluble e)

D 10. C 10.

Soluble d) C 9. B 9.

Insoluble c) D 8. D 8.

Insoluble b) D 7. A 7.

Soluble a) 2. B 6. A 6.

C 5. bonding - H d) D 5.

C 4. dipole - dipole c) A 4.

D 3. forces D 3.

D 2. dispersion London b) B 2.

A 1. dipole - ion a) 1. A 1.

Assessment More What's Know I What

What’s In

Intermolecular Forces Present in Substances

interaction dipole

Polar Linear HF 5.

- dipole forces, dispersion

bonding, London London bonding, -

forces dispersion London Nonpolar Linear

(Iodine)

I 4. 2

interaction dipole bent amine)

- dipole forces, dispersion Polar

Tetrahedral, Tetrahedral, (Methyl

bonding, London London bonding, - H

NH CH 3. 2 3

interaction dipole - dipole (Ozone)

Polar Bent

London dispersion forces, forces, dispersion London O 2.

interaction dipole alcohol)

bent

- dipole rces, fo dispersion Polar (Methyl

Tetrahedral, Tetrahedral,

bonding, London London bonding, - H OH CH 1.

Present Polarity Shape LEDS Substance

Forces Intermolecular

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What’s New

substances.

the of

e. The greater the intermolecular forces, the higher the boiling and melting points points melting and boiling the higher the forces, intermolecular the greater The e.

2 2 2 < At < Br < F d.

molecules. the among forces intermolecular the are greater the molecule

the

c. Intermolecular forces vary with the size of the molecule. The greater the size of of size the greater The molecule. the of size the with vary forces Intermolecular c.

2 forces dispersion London – At

2 2

forces; dispersion London – Br forces; dispersion London – F b.

points. boiling and melting highest the has Astatine a. 1

2 Activity

2 (Bromine) Br f.

12 5

(pentane) H C e.

5 PBr d.

3 c. NH c.

3 b. CHCl b.

NaCl a.

2 (Bromine) Br f.

12 5 (pentane) H C e.

PBr d. 3 c. NH c.

3 b. CHCl b.

3. 3.

NaCl a.

forces

2 2

(Bromine) : London dispersion dispersion London : (Bromine) Br forces; dispersion London : (Fluorine) F f.

forces

dispersion 12 5 12 5 (isopentane) : London London : (isopentane) H C forces; dispersion London : (pentane) H C e.

5 5 forces dispersion London : PBr forces; dispersion London : PCl d.

3 : 3 dipole - dipole : F CH ; bonding - H NH c.

3 4 dipole - dipole : CHCl forces; dispersion London : CCl b.

2. 2. 4 forces dispersion London : CH dipole; - dipole : NaCl

forces 2 2 (Bromine) : London dispersion dispersion London : (Bromine) Br forces; dispersion London : (Fluorine) F f.

forces dispersion

London

12 5 12 5

(isopentane) : : (isopentane) H C forces; dispersion London : (pentane) H C ( Pentane e.

5 5

forces dispersion on Lond : PBr forces; dispersion London : PCl d.

forces dispersion London

dipole, 3 : 3 - dipole : F CH ; forces dispersion London bonding, - H dipole, - dipole NH c.

forces

3 4 dipole, London dispersion dispersion London dipole, - dipole : CHCl forces; dispersion London : CCl b.

forces

1. 1. 4 : London dispersion dispersion London : CH forces; dispersion London dipole, - dipole : NaCl a.

1 Act.

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What Have I Learned

process. dissolution the in rule the is likes” dissolve

“Like molecules. of type the on depend will Solubility points. freezing and h. Remember that greater IMF will result to higher boiling, melting, melting, boiling, higher to result will IMF greater that Remember h.

tter. ma of properties physical the predicting for gauge

g. The strength of the predominating intermolecular forces will be the the be will forces intermolecular predominating the of strength The g.

forces. intermolecular greater the has one which tell also will compact

mination whether the structure of the molecule is extended or or extended is molecule the of structure the whether mination Deter f.

forces. intermolecular

molecule will tell which between the two substances has greater greater has substances two the between which tell will molecule

atoms and molecular geometry. If they are identical, then the mass of the the of mass the then identical, are they If geometry. molecular and atoms

the polarity of substances with the same number of of number same the with substances of polarity the Determine e.

prevail.

dipole forces of attraction will will attraction of forces dipole - ion then ionic is substance the If d.

molecules. the among forces intermolecular predominant

the are forces dispersion London then nonpolar, is substance the If c.

substances. all in present always

are forces dispersion London bonding can also form. form. also can bonding - H then F, N, O, to attached H has substance the

dipole forces are present. If If present. are forces dipole - dipole then polar, is substance the If b.

nonpolar. or polar is substance the whether first Determine a.

matter. of s propertie

the to IMF of effects the determine to take to considerations or Steps 3.

dipole – ion < bonding - H < dipole – dipole < dipole induced - dipole < LDF 2.

solubility. and points, freezing and melting, boiling, viscosity,

forces are surface tension, tension, surface are forces intermolecular by influenced properties The 1.

158

Additional Activities

ICL. of point boiling higher to resulting bonds the break

dipole bonds than LDF so more energy is required to to required is energy more so LDF than bonds dipole -

dipole the

2 dipole forces in ICl. It’s harder to break break to harder It’s ICl. in forces dipole - dipole while

Br in prevail 2 ar. London dispersion forces forces dispersion London ar. pol is ICl while nonpolar is Br c.

3 3 3 . CHCl than point boiling higher a has CHBr thus , CHCl in

3 3 than than

CHBr in bonds the break to energy of amount greater needs It

3 3 . . CHCl in than greater is forces dispersion London the then ,

CHCl 3 greater than the mass of of mass the than greater is CHBr of mass the Since molecules.

and molecular geometry. Thus, the basis will be the masses of the the of masses the be will basis the Thus, geometry. molecular and

attraction. Both have the same number of atoms in the molecule molecule the in atoms of number same the have Both attraction.

dipole and London dispersion forces of of forces dispersion London and dipole - dipole have Both b.

HF. of point

higher boiling boiling higher to results This HCl. in bonds the than HF of bonds

interactions so greater amount of energy is needed to break the the break to needed is energy of amount greater so interactions

dipole dipole - dipole than stronger is bonding - H forces. dipole - dipole

a bonding while in HCl is is HCl in while bonding - H is HF in IMF prevailing The .

159

References

Shawn P.Shields. “Analyzing Strengths of Intermolecular Forces.” Accessed May 25, 2020. https://www.youtube.com/watch?v=kU5nRCB4jJ8

BCcampus. “Intermolecular Forces.” Accessed May 21, 2020. https://opentextbc.ca/chemistry/chapter/10-1-intermolecular-forces/

Chang, Raymond.2005. Chemistry (8th. Ed.).New York, NY: McGraw-Hill Education (Asia).

Chegg Study. “Textbook Solutions.” Accessed May 23, 2020. https://www.chegg.com/homework- help/explain-glycerol-viscous-water- acetone-less-viscous-water-gl-chapter-7-problem-99p- solution- 9780077274290-exc chemlibretexts. “Liquids and Intermolecular Forces (Summary).” Accessed May 21, 2020. https://chem.libretexts.org/Bookshelves/General_Chemistry/Map%3A_Che mistry_- _The_Central_Science_(Brown_et_al.)/11%3A_Liquids_and_Intermolecular_F orces/11.S%3A _ Liquids_and_Intermolecular_Forces_(Summary)chemlibretexts.

“Properties of Matter.” Accessed May 25, 2020. https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemist ry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chem istry)/Physical _Properties_of_Matter chemlibretexts. “Solubility and Intermolecular Forces.” Accessed May 21, 2020.https://www.google.com/search?q=solubility+and+intermolecular+forc es&oq=solubility+and+intermolecular&aqs=chrome.0.0j69i57j0l4.13287j0j8 &sourceid=chrome&ie=UTF-8

Clutch. “Formal Charges of Ozone.” Accessed May 25, 2020. https://www.clutchprep.com/chemistry/practice-problems/131828/what- are-the-formal-charges-in-o3-ozone

Clutch. “Lewis Structure of HF.” Accessed May 25, 2020. https://www.clutchprep.com/chemistry/practice-problems/110784/look- at-the-lewis- structure-for-hf-where-are-the-nonbonding-electrons

160

Clutch. “Molecular Geometry of CH3NH2.” Accessed May 25, 2020. https://www.clutchprep.com/chemistry/practice-problems/108201/what- is-the-molecular- geometry-about-nitrogen-in-ch3nh2

Elmhurst College. “Intermolecular Forces.” Accessed May 20, 2020. http://chemistry.elmhurst.edu/vchembook/160Aintermolec.html

Liberal dictionary. “Pentane.” Accessed May 23, 2020. https://www.liberaldictionary.com/pentane/

Nutrients Review.com. “Glycerin (Glycerol).” Accessed May 22, 2020. http://www.nutrientsreview.com/carbs/edible- glycerin.html

Quora. “What is the formula and structure of water?” Accessed May 24, 2020. https://www.quora.com/What-is-the-formula-structure-of-water

Study.com. “Ether: Preparations and Reactions.” Accessed May 20, 2020. https://study.com/academy/lesson/ether-preparation-reactions.html

161

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Physical Science

163

Physical Science Biological Macromolecules First Edition 2020

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Published by the Department of Education Angelica J. Macaraeg Secretary: Leonor Magtolis Briones Undersecretary: Diosdado M. San Antonio

Development Team of the Module

Writers: Amy B. Villar, Jennifer O. Tullao Editors: Robert G. Yumul Felipa A. Morada Reviewers: Ramonito O. Elumbaring, Angelica J. Macaraeg Felipa A. Morada Illustrator: Francis Victor A. Medrano Layout Artist: Mary Grace L. Asa Pamela A. Lalusin Management Team: Wilfredo E. Cabral, Regional Director Job S. Zape Jr., CLMD Chief Elaine T. Balaogan, Regional ADM Coordinator Susan DL. Oribiana, Schools Division Superintendent Lorna R. Medrano, CID Chief Edita T. Olan, EPS-in-Charge, LRMS

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164

Physical Science Biological Macromolecules

165

Introductory Message

For the facilitator:

Welcome to the Physical Science 11 Alternative Delivery Mode (ADM) Module on Biological Macromolecules.

In addition to the material in the main text, you will also see this box in the body of the module:

Notes to the Teacher This contains helpful tips or strategies that will help you in guiding the learners.

As a facilitator you are expected to orient the learners on how to use this module. You also need to keep track of the learners' progress while allowing them to manage their own learning. Furthermore, you are expected to encourage and assist the learners as they do the tasks included in the module.

166

For the learner:

Welcome to the Physical Science 11 Alternative Delivery Mode (ADM) Module on Biological Macromolecules!

The hand is one of the most symbolized part of the human body. It is often used to depict skill, action and purpose. Through our hands we may learn, create and accomplish. Hence, the hand in this learning resource signifies that you as a learner is capable and empowered to successfully achieve the relevant competencies and skills at your own pace and time. Your academic success lies in your own hands!

This module has the following parts and corresponding icons:

What I Need to Know This will give you an idea of the skills or

competencies you are expected to learn in the module.

What I Know This part includes an activity that aims to

check what you already know about the lesson to take. If you get all the answers correct (100%), you may decide to skip this module.

What’s In This is a brief drill or review to help you link

the current lesson with the previous one.

What’s New In this portion, the new lesson will be

introduced to you in various ways such as a story, a song, a poem, a problem opener, an activity or a situation.

What is It This section provides a brief discussion of the

lesson. This aims to help you discover and understand new concepts and skills.

What’s More This comprises activities for independent

practice to solidify your understanding and skills of the topic. You may check the answers to the exercises using the Answer Key at the end of the module.

What I Have Learned This includes questions or blank

sentence/paragraph to be filled into process what you learned from the lesson.

What I Can Do This section provides an activity which will

help you transfer your new knowledge or skill into real-life situations or concerns.

167

Assessment This is a task which aims to evaluate your

level of mastery in achieving the learning competency.

Additional Activities In this portion, another activity will be given

to you to enrich your knowledge or skill of the lesson learned. This also tends retention of learned concepts.

Answer Key This contains answers to all activities in the

module.

At the end of this module you will also find:

References This is a list of all sources used in developing this module.

The following are some reminders in using this module:

We hope that through this material, you will experience meaningful learning and gain deep understanding of the relevant competencies. You can do it!

168

Week

What I Need to Know

This module was designed and written with you in mind. It is here to help you explain how the structures of biological macromolecules such as carbohydrates, lipids, nucleic acid, and proteins determine their properties and functions. The scope of this module permits it to be used in many different learning situations. The language used recognizes the diverse vocabulary level of students. The lessons are arranged to follow the standard sequence of the course. But the order in which you read them can be changed to correspond with the textbook you are now using.

After going through this module, you are expected to:

1. distinguish between carbohydrates, proteins, lipids, and nucleic acids; 2. summarize the general characteristics of each biomolecule; and 3. relate the structures of the biomolecules with their properties.

169

What I Know

True or False. Read each statement carefully. Identify whether the statement is true or false. Write your answer on a separate sheet of paper.

______1. Carbohydrates contain carbon.

______2. Meat contains protein.

______3. Lipids are soluble in water.

______4. Proteins are made up of nucleotides.

______5. DNA is a nucleic acid.

______6. Sucrose is a disaccharide.

______7. Starch is composed of many glucose units.

______8. Fructose is also known as blood sugar.

______9. Keratin is easily dissolved in water.

______10. Proteins are made up of nucleotides.

______11. The heme group of hemoglobion contains iron.

______12. A nucleotide has three parts: nitrogenous base, sugar, and phosphate group.

______13. DNA has a double-helix structure.

______14. Triglyceride is a protein.

______15. Generally, unsaturated fatty acids remain solid at room temperature.

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Lesson 1 Biological Macromolecules

Biological macromolecules are large, organic molecule such as carbohydrates, lipids, proteins, and nucleic acids. Most of them are organic compounds and the functional group determines their chemical properties. Biomolecules have a huge variety of functions, such as energy storage, protection, etc. Now be ready with your journey to the different biomolecules, their structures, and functions found in your food.

Hello! I am your nutritionist for today. Go ahead and think for a

moment about your favorite food.

Analyze the Nutritional Facts of a food product given below and rank the nutrients needed by the following patients based on importance. A. a patient with hypertension B. a patient renal failure C. a patient with diabetes mellitus Nutrition Facts

Serving Size 32 g Serving Per Pack 1

Amount/Serving %RENI Total Calories 150 6% Calories from Fat 45 Total Fat 5g Saturated Fat 3g + Trans Fat 0g Cholesterol 3mg Sodium 170mg 35% Total Carbohydrates 23g Dietary Fiber 0g 0% Sugars 4g Protein 3g 4% Calcium 55mg 8% Iron 1mg 8%

171

What’s In

Food is a source of molecules that are needed for life. These are biological molecules. What you eat contains biomolecules. There are four biological molecules that make up all of life. Now, I have here a word hunt for your warm up.

Look for the following words in the puzzle: biomolecule, carbohydrate, lipid, protein, and nucleic acid.

F A T S H Y L I P I D P U P I A T E P R O T E R N U C L E I C A C I D O Y T K T L P D G O G O T C A R B O H Y D R A T E A R O A A H L E W V W I B I O M O L E C U L E N

You are really doing great! It seems that you are now ready for our first biomolecule.

Notes to the Teacher Ask learners to list examples of carbohydrate, lipid, protein, and nucleic acid. Add on the list sources that are not mentioned by the learners.

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What’s New

Activity 1.1 Macromolecule Plates and Glass

1. Write inside the first plate an example of food rich in carbohydrates that you have eaten a while ago and tell us what you feel after eating it.

What did you feel after eating the food rich in carbohydrates? ______

2. Write inside the second plate an example of food rich in lipids that you have eaten a while ago.

What did you feel after eating the food rich in lipids? ______

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3. Write inside the third plate an example of food rich in protein that you have eaten a while ago and tell us what you feel about what you have eaten.

What did you feel after eating the protein - rich food? ______

4. Write inside the glass the function of nucleic acids.

174

What is It

Terms and Definitions

Monosaccharide – simplest form of carbohydrates

Monomer – a molecule that can react with other molecule to form very large molecules or polymers

Peptide – short chain of amino acid monomer linked by peptide bonds

Hormones – special chemical messengers that are created by the endocrine gland

Amino acids – organic compounds that combine to form proteins

Enzymes – proteins which make the biochemical reaction occus in faster rate

Nucleotide – composed of three components: nitrogen-containing base, five-carbon sugar, and a phosphate group

Phospholipids - contain glycerol, two-fatty acids, and a phosphate group

Biological Macromolecules

1. Carbohydrates

The word carbohydrate may be broken down to carbon and hydrate, and this is due to the fact that most carbohydrates follow the formula Cn(H2O)n. Another term for carbohydrate is saccharide. Carbohydrates are classified either as simple or complex. Simple sugars are monosaccharide and disaccharides. Complex sugars are polysaccharides.

Carbohydrates are the primary source of energy in the human body. The different saccharides that humans eat are converted to glucose which can be readily used by the body. The excess carbohydrates taken into the body is converted to glycogen that is stored in the liver and in muscles.

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Monosaccharide (one saccharide)

Glucose used in dextrose, blood sugar; the form utilized by the human body

Galactose found in milk and milk products

Fructose found in fruits and honey

Disaccharides (two saccharides)

Maltose glucose + glucose found in malt Sucrose glucose + fructose found in regular table sugar, sugarcane, and sugar beet Lactose glucose + galactose found in milk and milk products

Polysaccharides (many saccharides)

Starch / Amylose storage form of glucose in plants

Amylopectin storage form of glucose in plants

Glycogen storage form of glucose animal; stored in the liver and muscles Cellulose structural material in plants--cell wall in wood, wood fiber cannot be digested by humans

Carbohydrates

They are made from carbon, hydrogen, and oxygen.

Monomer: saccharides

Examples: rice, cereal, potatoes, fruits, pastas

Function: main energy source of the body

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Did you know that?

Marathon runners, tri-athletes, and other runners consume carbohydrates for weeks leading up to a big event. They call it “carbo-loading”. What’s the point? As the athletes consume massive amounts of starch and pasta, the energy begins to store up in their body, saving itself for use during the event.

2. Lipids or Fats

Lipids or fats are important nutrients in your body but eating too much unhealthy fats such as saturated fats and trans fats can lead to heart disease and obesity. Lipids also serve other functions such as material for cell membrane, insulation to maintain body temperature, aid in digestion, and as signal molecules.

There are different common classifications of lipids: triglyceride, phospholipid, wax, and steroid. The lipid family is one of the most varied in terms of structure but they share the common property - being insoluble in water.

Fat and oil are the most common examples of lipids. They are under triglycerides because they are composed of glycerol and three fatty acids.

Fat refers to solid triglyceride usually from animal sources such as meat, milk, butter, margarine, eggs, and cheese. Oil refers to liquid triglycerides from plant sources. Examples are olive oil, corn oil, sunflower oil, and soybean oil. Animal fats contain high percentages of saturated fatty acids while plant oils are mostly unsaturated fatty acids.

Lipids They are made from carbon, hydrogen, and oxygen They are soluble (dissolve) in oil but are insoluble (don’t dissolve) in water.

Examples: fats and oils

Function: long-term storage of energy in the body

Monomer: fatty acid

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3. Proteins

Proteins are composed of four elements, namely: carbon, hydrogen, oxygen, and nitrogen. Sulfur is sometimes also found in proteins. If carbohydrates are made up of saccharides, proteins are made up of amino acids.

Examples of proteins and their functions are:

1. Keratin is a structural protein found in hair, skin, and nails. 2. Fibroin / Silk protein - Fibroin is found in silk. Silk has a smooth and soft texture. It is one of the strongest natural fibers that have high resistance to deformation. It is also a good insulating material. 3. Collagen is a major insoluble fibrous protein found in connective tissues such as tendons, ligaments, skin, cartilage and the cornea of the eye. It comprises as much as 30% of proteins in animals. 4. Enzymes function to catalyze chemical reactions. They either speed up a reaction, lower the needed energy for a reaction to take place, or bind substances to their specific partners. Examples of enzymes a. Lipase - help in digestion of fats b. Pepsin - help in breaking down proteins into peptides (smaller units) c. Sucrase - also called invertase; help in the digestion of sugars and starches 5. Myoglobin is a polypeptide that stores oxygen in muscles. It contains a heme group which has an iron where the oxygen is stored.

Proteins

They are made from carbon, hydrogen, oxygen, nitrogen and sometimes sulfur. Proteins are made up of amino acids combined through a dehydration link called a peptide bond. Monomer: amino acid

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4. Nucleic Acids

Nucleic acids play an essential role in the storage, transfer, and expression of genetic information. Nucleic acid was discovered by a 24-year old Swiss physician named Friedrich Miescher in 1868. He was puzzled that an unknown substance in white blood cells did not resemble carbohydrates, proteins, or lipids. He was able to isolate the substance from the nucleus and initially called it nuclein. He eventually was able to break down nuclein into protein and nucleic acids. He found out that nucleic acids contain carbon, hydrogen, oxygen, nitrogen, and phosphorus.

The most common examples of nucleic acids are DNA (deoxyribonucleic acid) and RNA (ribonucleic acid). DNA is a nucleic acid that carries the genetic code of organisms. It is fondly termed as the blueprint of life. RNA, on another hand, carries the information from the DNA to the cellular factories for the synthesis of proteins called ribosome. If carbohydrates are composed of saccharide units and proteins of amino acids, nucleic acids are composed of nucleotides. Nucleic acids are also known as polynucleotides.

Three parts of nucleotide: 1. Nitrogenous base 2. Five-carbon carbohydrate or sugar 3. Phosphate group

Nucleic Acids

They are made from carbon, hydrogen, oxygen, nitrogen, and phosphorus.

Monomer: nucleotide

Examples: DNA and RNA

Function: DNA carries the genetic code of organisms. RNA, carries the

information from the DNA to ribosomes to produce proteins.

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Structures of the Different Biomolecules

Remember this mnemonic device of biomolecules: CHO CHO CHON CHONP

C stands for the element Carbon N stands for the element Nitrogen H stands for the element Hydrogen P stands for the element Phosphorus O stands for the element Oxygen

Again, say the mnemonic device.

CHO CHO CHON CHONP!

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What’s More

Activity 1.2 Meal Plan

Think of a 3 – day healthy meal plan for a teenager like you following the table below. Make sure that you choose the right kind of food containing carbohydrates, proteins, and lipids.

3 – Day Meal Plan

Day 1 Day 2 Day 3 Breakfast Morning Snack Lunch Afternoon Snack Dinner Dessert

What I Have Learned

Activity 1.3 Maze Runner

I have a friend named Bimol. He needs our help

in finding the right way to go back to his house. In order to help him, you need to answer some questions about biomolecules.

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Hello! My name is Bimol. I have a problem. I cannot go back home. Please help me by answering the questions.

Carbohydrates Lipids

What elements are they composed of? What elements are they composed of?

______

What is the monomer? What is the monomer?

______

What is its function for the body? What is its function for the body?

______

Write two examples: ______Write two examples: ______

Proteins Nucleic Acids

What elements are they composed of? What elements are they composed of?

______

What is the monomer? What is the monomer?

______

What is its function for the body? What is its function for the body?

______

Write two examples: ______3 Write two examples: ______4

Thanks for helping Bimol!

HOME

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What I Can Do

Activity 1.4 Amazing Lunch

Now, you already know the different biomolecules. Oops! I heard something in your stomach. Since you did great, I have a reward for you. Help me to prepare your lunch by encircling the words related opposite to each biomolecule on the left side.

BIOMOLECULES

Carbohydrates rice oil pork apple sugar nitrogen

Lipids wax fish fatty acid mango lemon

Proteins beef potato amino acid avocado

Nucleic Acids bread chicken carbon oxygen phosphorous

Complete the table filling out the required information. Identify the disorder/disease, related macromolecule and its function based on the given scenario.

1. Covida, a grade 12 student experienced excessive sweating, frequent urination, feeling very thirsty and hungry. She was not able to attend her class during that day. She was rushed in the hospital and upon examining her blood sugar it was found out that it is above its normal value.

2. One of the students of Mr. Corona shared her story when she was hospitalized at the age of three. She showed her picture with enlarged tummy, loss of muscle mass and inflamed patches on her skin. She even mentioned that she was also irritable and had failure to grow in height according to her mother.

3. While presenting the lesson on Circulation and Gas Exchange, the teacher of Pandemic Integrated National High School complains shortness of breath, tightness and aching sensation in his chest that radiates to his neck and jaw. Disorders/ Diseases Related Macromolecules Function of Macromolecules

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Assessment

Multiple Choice. Read and analyze the given statements below. Write the chosen letter on a separate sheet of paper.

1. Which group of biomolecules carries and passes on the hereditary information of the organism? a. carbohydrates b. lipids c. nucleic acids d. proteins

2. Which biomolecules are significant components of the cell membrane? a. carbohydrate and nucleic acid b. lipid and nucleic acid c. nucleic acid and protein d. protein and lipid

3. What are the elements that make up carbohydrates? a. C and H b. C, H and N c. C, H and O d. C, H, O and N

4. Which organic molecule is soluble in water and serves as a quick source of energy? a. carbohydrates b. lipids c. nucleic acids d. proteins

5. In which group of biomolecule do waxes that coat some organisms belongs? a. carbohydrates b. lipids c. nucleic acids d. proteins

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6. Which of the following is NOT a lipid? a. hemoglobin b. fat c. steroid d. triglyceride

7. Which of the following is considered as the building block of proteins? a. amino acids b. nucleic acids c. nucleotides d. polypeptides

8. Which of the following is the storage form of excess glucose in the body, particularly in the liver and muscles. a. creatinine b. glycogen c. hemoglobin d. uric acid

9. Which of the following is a monosaccharide found in dextrose? a. fructose b. galactose c. glucose d. lactose

10. Which is an example of saturated fat? a. butter b. corn oil c. olive oil d. sunflower oil

11. Which is termed as the blueprint of life? a. deoxyribonucleic acid b. fatty acid c. nucleic acid d. ribonucleic acid

12. Proteins are mainly composed of four elements, namely: carbon, hydrogen, oxygen and what other element? a. magnesium b. nitrogen c. phosphorous d. sodium

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13. Which of the following is a major insoluble fibrous protein found in connective tissues such as tendons, ligaments, skin, cartilage and the cornea of the eye? a. albumin b. collagen c. keratin d. pepsin

14. Which polypeptide carries oxygen in muscles? a. enzyme b. heme c. lipase d. myoglobin

15. Which is not a part of a nucleotide? a. nitrogenous base b. phosphate group c. ribonucleic acid d. sugar

Additional Activities

Activity 1.5 Biomolecule Poem

Summarize the topics and creatively translate them into a poem describing what you have learned about biomolecules. Write your answer on a separate answer sheet.

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Answer Key

15. D 14.

B 13.

12.

A 11.

10. C 9.

B 8.

A 7.

A 6.

A 4.

C 3.

D 2.

C 1. . vary may Answers

Assessment

Additional Activities Additional

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egg sugar crops, root

Examples fish nuts, products, grains, fruits,

_ _ _ nuts, butter, Oil, dairy Meat, rice, Bread,

molecules Signal ;Antibody

membrane; membrane; molecule

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digestion; digestion; molecule; plants in material

life of Code

heat; Aid in in Aid heat; Storage Enzyme; Structural body;

Used/Function synthesis; body Maintaining material; the in energy

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What I Can Do

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much lipids or fats in the body narrow blood blood narrow body the in fats or lipids much Infarction

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which gives energy. Increased carbohydrate intake intake carbohydrate Increased energy. gives which

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References

Commission on Higher Education. Teaching Guide for Senior High School: Physical Science. Book. https://drive.google.com/file/d/0B869YF0KEHr7SHFGVG5mVFFhcXc/view. Creative Commons Attribution-NonCommercial-ShareAlike 4.0

Wikipedia.2020. “Carbohydrate loading.” Last modified April 19, 2020. https://en.wikipedia.org/wiki/carbohydarateloading

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For inquiries or feedback, please write or call:

Department of Education - Bureau of Learning Resources (DepEd-BLR)

Ground Floor, Bonifacio Bldg., DepEd Complex Meralco Avenue, Pasig City, Philippines 1600

Telefax: (632) 8634-1072; 8634-1054; 8631-4985

Email Address: [email protected] * [email protected]

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Physical Science

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Physical Science Collision Theory and the Rate of Chemical Reaction First Edition 2020

Published by the Department of Education Secretary: Leonor Magtolis Briones Undersecretary: Diosdado M. San Antonio

Development Team of the Module

Writers: Marilou T. Flores, Ma. Clarinda N. Medequiso Editors: Robert G. Yumul Felipa A. Morada Reviewers: Ramonito O. Elumbaring, Angelica J. Macaraeg Felipa A. Morada Illustrator: Francis Victor A. Medrano Layout Artist: Mary Grace L. Asa Pamela A. Lalusin Management Team: Wilfredo E. Cabral, Regional Director Job S. Zape Jr., CLMD Chief Elaine T. Balaogan, Regional ADM Coordinator Susan DL. Oribiana, Schools Division Superintendent Lorna R. Medrano, CID Chief Edita T. Olan, EPS-in-Charge, LRMS

Department of Education – Region IV-A CALABARZON

Office Address: Gate 2 Karangalan Village, Barangay San Isidro Cainta, Rizal 1800 Telefax: 02-8682-5773/8684-4914/8647-7487 E-mail Address: [email protected]

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Physical Science Collision Theory and the Rate of Chemical Reaction

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Introductory Message

For the facilitator:

Welcome to the Physical Science Grade 11 Alternative Delivery Mode (ADM) Module on Collision Theory and the Rate of Chemical Reaction!

In addition to the material in the main text, you will also see this box in the body of the module:

Notes to the Teacher This contains helpful tips or strategies that will help you in guiding the learners.

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For the learner:

Welcome to the Physical Science Grade 11 Alternative Delivery Mode (ADM) Module on Collision Theory and the Rate of Chemical Reaction!

This module has the following parts and corresponding icons:

What I Need to Know This will give you an idea of the skills or

competencies you are expected to learn in the module.

What I Know This part includes an activity that aims to

check what you already know about the lesson to take. If you get all the answers correct (100%), you may decide to skip this module.

What’s In This is a brief drill or review to help you link

the current lesson with the previous one.

What’s New In this portion, the new lesson will be

introduced to you in various ways such as a story, a song, a poem, a problem opener, an activity or a situation.

What is It This section provides a brief discussion of the

lesson. This aims to help you discover and understand new concepts and skills.

What’s More This comprises activities for independent

practice to solidify your understanding and skills of the topic. You may check the answers to the exercises using the Answer Key at the end of the module.

What I Have Learned This includes questions or blank

sentence/paragraph to be filled in to process what you learned from the lesson.

What I Can Do This section provides an activity which will

help you transfer your new knowledge or skill into real life situations or concerns.

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Assessment This is a task which aims to evaluate your

level of mastery in achieving the learning competency.

Additional Activities In this portion, another activity will be given

to you to enrich your knowledge or skill of the lesson learned. This also tends retention of learned concepts.

Answer Key This contains answers to all activities in the

module.

At the end of this module you will also find answer key to serve as your guide to check your level of understanding.

References This is a list of all sources used in developing this module.

The following are some reminders in using this module:

1. Use the module with care. Do not put unnecessary mark/s on any part of the module. Use a separate sheet of paper in answering the exercises. 2. Do not forget to answer What I Know before moving on to the other activities included in the module. 3. Read the instruction carefully before doing each task. 4. Observe honesty and integrity in doing the tasks and checking your answers. 5. Finish the task at hand before proceeding to the next. 6. Return this module to your teacher/facilitator once you are through with it. If you encounter any difficulty in answering the tasks in this module, do not hesitate to consult your teacher or facilitator. Always bear in mind that you are not alone.

We hope that through this material, you will experience meaningful learning and gain deep understanding of the relevant competencies. You can do it!

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Week

What I Need to Know

This module was designed and written with you in mind. It is here to help you master the use of simple collision theory to explain the effects of concentration, temperature, and particle size on the rate of reaction. The scope of this module permits it to be used in many different learning situations. The language used recognizes the diverse vocabulary level of students. The lessons are arranged to follow the standard sequence of the course. But the order in which you read them can be changed to correspond with the textbook you are now using.

The module is divided into two lessons, namely:  Lesson 1 – Collision Theory  Lesson 2 – Factors Affecting the Rate of Chemical Reactions

After going through this module, you are expected to: 1. define collision theory and describe how it affects the chemical reaction; and 2. explain the different factors affecting the rate of reaction.

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What I Know

Choose the letter of the best answer. Write the chosen letter on a separate sheet of paper.

1. A chemical change that occurs when two or more substances combine to form a new substance. a. Activation Energy b. Chemical Kinetics c. Chemical Reaction d. Product

2. The measure of how fast is the change in the concentration of the reactants or products in a chemical reaction. a. Activation Energy b. Activation Rate c. Chemical Reaction d. Concentration

3. The substance that enter into and is altered in the course of a chemical reaction. a. Catalyst b. Enzyme c. Product d. Reactant

4. The number of particles present in a given volume of solution. a. Catalyst b. Concentration c. Product d. Temperature

5. The measure of how fast or slow a reaction happens. a. Activation Energy b. Collision theory c. Particle Size d. Rate of Reaction

6. Condition that needs to be met for a chemical reaction to occur. a. Substance must be homogeneous. b. Temperature should be kept constant. c. Particles should maintain a certain distance to each other. d. Particles in the substance must collide and have enough energy.

7. The factor that would NOT affect the rate of chemical reaction. a. Concentration b. Humidity c. Particle Size b. Temperature

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8. The factor that will slow down the rate of chemical reaction. a. Manual stirring of the substance. b. Placing substance in a hot water. c. Placing catalyst in iced water. d. Placing reactants in ice bath.

9. The factor that does NOT show evidence of chemical reaction. a. Absorption of heat b. Change of color c. Change of size d. Liberation of heat

10. The measure of the average kinetic energy of the particles in an object a. Energy b. Humidity c. Temperature d. Thermometer

11. The substance formed as a result of a chemical reaction. a. Product b. Reactant c. Resistance d. Substrate

12. The measure of how much exposed area a solid object has, expressed in square units. a. Volume b. Surface c. Surface Area d. Concentration

13. The substance that is dissolved in a solution. a. Solid b. Solute c. Solvent d. Substance

14. The component of a solution that is present in the greater amount. a. Sample b. Solute c. Solvent d. Substance

15. A form of matter that has definite composition and distinct characteristics. a. Atoms b. Compound c. Mixture d. Substance

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Lesson 1 Collision Theory

Chemical reactions have been a part of this world ever since everything began. From Big bang to the present day, everything happening around us has something to do with chemical reactions and chemical processes. Chemical reactions are commonly observed in our daily lives such as in cooking, eating, cleaning and in processes like respiration, corrosion and fermentation. Even how our body lives and grows are all but some of the many chemical reactions that take place, although you may not recognize them. This is the reason we need to understand how chemical processes take place, be it naturally occurring or not.

This lesson will help enhance your understanding about how chemical reaction occurs and what are the different factors affecting chemical reaction.

What’s In

Simple Recall

Chemical or Physical Change?

Directions: Identify the type of change that id describe in each item. Write the word Physical or Chemical on the right side of the picture.

1. Baking a Cake

2. Burning Paper

3. Preparing hot coffee

4. Dissolving sugar in water

5. Mixing paint to make a new color

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What’s New

Picture Analysis

When we talk about reactions in science, what does that make you think of? Write out a list of your ideas about this picture. ______

______

Complete the sentence about the word Reaction.

A reaction is when ______.

What is It

The Collision Theory All substances are comprised of millions of tiny particles in constant motion. These particles are constantly colliding with each other. Not all collisions between particles of reactants result to generation of a product. There are two factors that determine whether a reaction will occur between two particles that are colliding: 1. Substances or particles of reactants must physically collide with enough energy

2. Substance or particles must come into contact or collide in the correct orientation (facing the correct way).

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The collision theory states that reacting substances must come into contact (collide) with enough activation energy, and in the correct orientation (facing the correct way), so that their electron shells can rearrange to form the products of the reaction. Therefore, any factor which changes the frequency or energy of the collisions will change the rate of the reaction.

Try to analyze the illustrations given below:

As shown on the picture, the diatomic Nitrogen gas reacts with diatomic Oxygen gas to yield two molecules of Nitrogen Oxide. The shared atoms form a bond by completing the valence shells of both atoms.

A chemical reaction does not take place if the collision between molecules does not have sufficient energy to break the bonds in the reactants and if the molecules are not properly oriented.

Figure 1 Figure 2

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As shown in figure 2, no reaction can take place between two particles if they are far apart. To form new bonds, atoms must come in contact with each other and have correct relative orientations so that the correct bonds are broken, atoms transfer to

the correct positions (see Figure 1).

What is a Chemical Reaction?

When two particles collide, sometimes a chemical reaction can occur, which means the bonds between two or more particles are broken and reformed, creating one or more new substances. The substances or particles that enter and is changed in the chemical reaction are called reactants and the substances that are formed are called products.

Let us look at the net chemical reaction in photosynthesis:

The reactants (left part of the equation) are carbon dioxide, water, and light while the products (right side of the equation) are sugar and oxygen. But for a chemical

reaction to occur, several things must happen:

1. The particles must come into contact with one another or collide.

2. When they collide, the particles must be lined by correctly so that the right parts of the atoms or molecules are exposed. If they are not oriented correctly, no chemical reaction will take place. 3. The particles must collide with enough energy to break their chemical bonds. The amount of energy that must be available for a reaction to occur is referred to as the activation energy. The reaction rate of a chemical reaction is a measurement of the increase in the concentration of a product or the decrease in the concentration of a reactants as the reaction proceeds over time. Keep in mind that not all reactions occur at the same speed. Some are very slow while others are fast.

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The rate of reaction also depends on the type of molecules that combine. If there are low concentrations (does it refer to the terms in boldface in the previous statement? Type od molecule and concentration are not related to each other, maybe the number of molecules  of an element or compound, the reaction will be slower.

Lesson Factors Affecting the Rate 2 of Reaction

1. Activation Energy The activation energy refers to the minimum energy required for a reaction to take place. When a collision provides energy equal to or greater than the activation energy, a product can form. On the other hand, if the energy of the particles is less than the activation energy, the collision may not effective, and they just could bounce off each other unchanged.

The figure above shows a man trying to push a rock over the cliff. For the man to push the rock, he needs to have enough energy. If the man does not have enough energy, the rock will not move down the cliff. This energy needed for the man to push the rock over the cliff represents the activation energy. Can you think of another example to show how activation energy works? ______

2. Temperature

Temperature refers to the average kinetic energy of the particles in an object. As a rule of thumb, a rise in temperature of 10 0C doubles the reaction rate. The rate of a chemical reaction increases with increasing temperature. As the temperature increases, collision between atoms and molecules becomes faster resulting to build up of more energy. The increased kinetic energy will equal to or exceed the activation energy resulting to more collisions giving rise to a reaction.

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Let us try to apply: Arrange the following samples according to the rate of solubility of sugar. (1 -fastest, 3-slowest)

Cold water Hot water Tap water ______

3. Concentration

The rate of a chemical reaction is affected by the concentration of reacting substances. The term concentration refers to the number of particles present in a given volume of solution. Concentration may also mean a measure of how much of the solute (something to be dissolved) is dissolved in a solvent (dissolving medium) to form a homogeneous mixture. So, a higher concentration means there is more of the solute in the solution. If the concentration of the reactant is increased, the rate of reaction also increases. When the number of particles of the reactant is increased, there is a great chance for particles to collide.

To illustrate:

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Now, let us try to do Picture Analysis:

Based on the Kinetic Molecular Theory (KMT) and properties of matter, why do you think there is less collision on the left side while there is more collision on the right side? ______

What can you deduce (conclude) about the effect of concentration on the rate of chemical reaction? ______

4. Surface Area and Particle Size Surface area is the measure of how much exposed area a solid object has, expressed in square units. In a reaction between a solid and a liquid, the more finely divided a solid is, the faster is the rate of reaction. Likewise, as you powdered a solid, its surface area becomes greater, thus the particles have higher chance of colliding and faster reaction happens.

To understand this further, try to analyze the picture and answer the questions below:

Figure 1 Figure 2

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How many reactant particles can be seen on Figure 1? ______Which do you think is the solid particle on Figure 1? ______What have you observed to the reactant particles in Figure 2? ______In which container will the solid particle dissolve faster and why? ______

What’s More

Activity 1.1 Factors affecting Reaction Rates

The rate at which reactants are consumed and products are formed during chemical reactions vary greatly. In this part of the module, you will discover how the different factors, such as concentration, temperature and particle size affect the rate of chemical reactions.

The following video links are experiments that you will watch and observe before answering the “Activity Assessment.” A. Effects of concentration: https://www.youtube.com/watch?v=o_TJEHzjBLM B. Effects of Temperature: https://www.youtube.com/watch?v=izqJkdj1d4U C. Effects of Particle Size: https://www.youtube.com/watch?v=kQtKRBL3rJY

Activity 1.2 Guide Questions

Directions: Answer briefly and concisely the following questions.

PART A: Effects of Concentration

1. What evidence shows that reaction occurs? ______2-3. Compare the rate of formation of Hydrogen gas in tube A that contains diluted Hydrochloric acid (HCl) with that of tube B containing concentrated Hydrochloric acid (HCl). ______

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4-5. Explain the effects of concentration on the rate of chemical reaction. ______

6. Show the correct chemical equation for the reaction of Magnesium (Mg) ribbon and Hydrochloric (HCl) acid. ______

PART B: Effects of Temperature

7. In which temperature of Oxalic acid (C2H2O4) and Sulfuric acid (H2SO4) mixture

did the Potassium Permanganate (KMnO4) dissolves faster? ______

8-9. What evidence shows that a fast reaction occurs? ______

10-11. How does temperature affect the rate of chemical reaction? ______

PART C: Effects of Particle Size

12-13. Compare the speed reaction of powdered Calcium Carbonate (CaCO3) with that of a lump of Calcium Carbonate placed in water? ______

14-15. How does particle size affect the rate of chemical reaction? ______

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What I Have Learned

SENTENCE COMPLETION

Directions: Complete the group of words to form relevant ideas about the lesson.

1. According to the collision theory, there are three (3) requirements for a reaction to occur: these are ______, ______and ______.

2. The factors that can affect the rate of reaction are ______, ______, ______and ______.

3. Increasing the concentration of reactants in a solution ______the frequency of collision of particles and the rate of reaction.

4. Increasing the concentration means, there is more of ______in the solution.

5. Increasing the temperature ______the collision of particles.

6. Increasing the temperature ______the kinetic energy of particles.

7. The greater the size of particles, the ______is the surface area.

8. The smaller the size of particles, the ______is the surface area.

9. Remember, not all reactions happen at the same speed. Some are ______while others are ______.

What I Can Do

Create your own 5-minute experiment video by choosing one of the factors discussed in this lesson.

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Rubric for Grading The video will be scored from 1 to 5, with 5 being the highest. The criteria for grading are as follows:

Criteria Expectations

Visuals The video is clear and engaging. Camera shots tell the story visually and no lighting problems.

Audio Loudness and dialogue are balanced. Spoken words show confidence and are convincing.

Content Delivery of content is precise and complete. Emphasis given should be based on the discussion.

Timeliness The video should consume the required 5-minutes. For every less or added minute/s, points will be deducted.

Assessment

PART A. MODIFIED TRUE OR FALSE

Directions: Write the word TRUE if the statement is correct. If FALSE, change the italicized word or group of words to make the statement correct.

______1. Decreasing the concentration of the reactants increases the collision frequency between reacting particles.

______2. Increasing the concentration of a substance increases the kinetic energy of the particles that make up the substance.

______3. Increasing the surface area of the reactant, increases the rate of the reaction.

______4. Raising the temperature of the reaction increases the rate of the reaction by increasing the energy of the collisions between reacting particles.

______5. If the reactant particles collide with less than the activation energy, the particles bounce back, and no reaction will occur.

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PART B. IDENTIFICATION

Directions: Identify what factor affects the rate of chemical reaction in the following situations. Use the choices below by writing the correct letter before the number.

A. Temperature B. Concentrations C. Particle Size

______6. The food was refrigerated. ______7. A coal dust explosion happens in mines. ______8. Acid rain erodes marble fast. ______9. Two antacid tablets neutralize acids faster than one tablet. ______10. Kindling is used to start a fire.

PART C. MULTIPLE CHOICE

Directions: Encircle the LETTER of the correct answer.

11. What condition/s must be met in order for a chemical reaction to occur? A. Collision with proper orientation B. Sufficient activation energy C. Adding more reactant particles D. Both A and B

12. Which of the following would NOT increase the rate of reaction? A. Increasing the temperature B. Adding catalyst C. Increasing the volume D. Increasing the concentrations

13. Suppose you dissolve Zinc (Zn) in Hydrochloric acid (HCl) and add more acid than usual. Then drop pieces of Zinc. What factor does NOT affect the rate of the reaction? A. Surface area of the Zinc B. Concentration of the reactant C. Temperature of the solution D. Amount of Hydrochloric acid

14. Activation energy is the amount of energy required to ______A. Break the bonds between the reacting molecules B. Make the reacting particles collide C. Form the bonds between the product molecules D. Convert the reactant to a single product

15. Why does a candle burn more rapidly when placed in an open jar than in air? What accounts for this reaction? A. Higher Oxygen concentration B. Greater surface area of the jar C. Increasing the surrounding temperature D. Length of the candle

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Additional Activities

Now is the time for you to explore your knowledge about collision theory and the factors affecting the rate of chemical reaction. Only short answers are needed.

1. Use the collision theory to explain why a lump of sugar is better to use in hot cup of tea, but granulated sugar is better to use in iced tea. ______

2. Suppose you held a lighted match to a solid piece of wood and another match to a pile of wood shavings. Which form of wood would catch fire more easily and why? ______

WORD SEARCH ACTIVITY

Directions: Find and encircle the missing words hidden in the grid. The words may be hidden in any direction.

Activation Collision Energy Particle size Product Reactant Reaction Solute Temperature Theory

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Answer Key

3. . temperature high with increases reaction of rate The

. fast disappears color pink The 2.

s. temperature high in or hot In 1.

Temperature of Effects

6. H + →MgCl 2HCl + Mg 2 2

(continuation) 1.2 Activity More What’s

. The rate of reaction increases with increase of concentration of the reactants the of concentration of increase with increases reaction of rate The . 5 - 4

acid. ydrochloric H diluted containing A tube in than acid ydrochloric H concentrated

ydrogen gas is higher in the boiling tube B containing containing B tube boiling the in higher is gas ydrogen H of formation of rate The 3. - 2

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Concentration of Effects

1.2 Activity More What’s

Figure 2 because the particles are smaller which increases the surface area surface the increases which smaller are particles the because 2 Figure

smaller pieces; pieces; smaller into broken are they atom; Magnesium 3; - Size of particle/surface area particle/surface of Size

(continuation) it Is What

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particles een betw collision

the particles on the left side has more spaces between them so there is less less is there so them between spaces more has side left the on particles the - Concentration

3 - water Cold 2; - water Tap 1; - water Hot - Temperature

force. and energy

a cyclist going up a steep road. Or any activity that requires exerting exerting requires that activity any Or road. steep a up going cyclist a - gy Ener Activation

It Is What

C 9.

elements D 8.

A bond was formed between between formed was bond A B 7.

D 15. D 6.

compound. a form to elements Chemical 5. C 14. D 5.

There is combining of two or more more or two of combining is There 2. Physical 4. B 13. B 4.

Physical 3. C 12. D 3.

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color, of Change 1. Chemical 1. C 10. C 1.

New What’s In What's Know I What

213

SEARCH WORD

(cont.) Activities Additional

reactant creating greater collision and increasing the rate of chemical reactions. chemical of rate the increasing and collision greater creating reactant

1. other other to exposed are particles more because easily more fire catch will shavings Wood

(cont.) Activities Additional

because more particles are exposed to water. to exposed are particles more because

Granulated sugar increases the dissolving rate rate dissolving the increases sugar Granulated energy. more gaining faster, collide

particles particles he t making temperature in increase with increased is rate Reaction

In hot tea, the lump of sugar dissolves faster because of the temperature. temperature. the of because faster dissolves sugar of lump the tea, hot In

Activities Additional

Fast/Faster Slow/Slower, 9.

Greater 8. 10.

Smaller 7. C 10.

Increases 6. B 9.

Increases 5. B 8.

Solute 4. C 7.

ses Increa 3. A 6.

Area A 15. True 5.

Concentration and Particle Size/Surface Size/Surface Particle and Concentration B 14. True 4.

Activation Energy, Temperature, Temperature, Energy, Activation 2. D 13. True 3.

Activation C 12. True 2.

Collision of particles, Orientation and and Orientation particles, of Collision 1. D 11. increasing 1.

Assessment Learned Have I What

reaction. of rate the faster the particles, reacting

mical reaction. The smaller the size of the the of size the smaller The reaction. mical che of speed the increasing thus increases

When particle size decreases, the total surface area exposed to reacting particles particles reacting to exposed area surface total the decreases, size particle When

CaCO of lump a than faster dissolves ) (CaCO arbonate C alcium C Powdered 1. 3. 3

Size Particle of Effects

(continuation) 1.2 Activity ore M What’s

214

References

“Activation Energy and Temperature Dependence.” https://courses.lumenlearning. com/boundless-chemistry/chapter/ activation -energy-and-temperature- dependence/. Retrieved May 24, 2020.

“Activation Energy. What do you want to activate?” The Mazemaster Blog. May 14, 2012. https://agritourismspeaker.com/2012/05/14/activation-energy- what-do-you-want-to-activat/. Davidson, Ashlie. “Collision Theory of Reactions” https://slideplayer.com/ slide/7517587/. Retrieved May 25, 2020. King, Lorin. “Chemical and Physical Reactions” Reactions Power Point. April 29, 2011. https://betterlesson.com/community/document/156325/reactions- power-point-pptx.

Klepner, Jackie. “What is the correct equation for photosynthesis?” January 28, 2018.https://www.quora.com/What-is-the-balanced-equation-rate- photosynthesis “Making Reactions Faster: Factors Affecting Rates of Reaction. February 17, 2016. https://www.compoundchem.com/2016/02/17/rate-of-reaction/. Padua, Alicia L., Ma. Cristina D. Padolina, Ricardo M. Crisostomo, and Marie Jessica

B. Alumaga. Physical Science. Vibal Group Inc., 2016.

“Rate of Reaction -Factors” 2015. https://www.pathwayz.org/Tree/ Plain/ RATES +OF +REACTION+-+FACTORS. Retrieved May 24, 2020. “Rate of Reaction” 2018.http://www.chem4kids.comfiles/react_rates.html. Retrieved May 25, 2020. Rodgers, Elia. 2020. Reaction Rate and Equilibrium-Power point Presentation. https://www.slideserve.com/elia/reaction-rate-and-equilibrium. Retrieved May 25, 2020.

215

For inquiries or feedback, please write or call:

Department of Education - Bureau of Learning Resources (DepEd-BLR)

Ground Floor, Bonifacio Bldg., DepEd Complex Meralco Avenue, Pasig City, Philippines 1600

Telefax: (632) 8634-1072; 8634-1054; 8631-4985

Email Address: [email protected] * [email protected]

216

Physical Science

217

Physical Science Catalyst First Edition 2020

Published by the Department of Education Secretary: Leonor Magtolis Briones Undersecretary: Diosdado M. San Antonio

Development Team of the Module

Writer: X-handi B. Fallarna Editors: Robert G. Yumul Felipa A. Morada Reviewers: Ramonito O. Elumbaring, Angelica J. Macaraeg Felipa A. Morada Illustrator: Francis Victor A. Medrano Layout Artist: Mary Grace L. Asa, Pamela A. Lalusin Management Team: Wilfredo E. Cabral, Regional Director Job S. Zape Jr., CLMD Chief Elaine T. Balaogan, Regional ADM Coordinator Susan DL. Oribiana, Schools Division Superintendent Lorna R. Medrano, CID Chief Edita T. Olan, EPS-in-Charge, LRMS

Department of Education – Region IV-A CALABARZON

Office Address: Gate 2 Karangalan Village, Barangay San Isidro Cainta, Rizal 1800 Telefax: 02-8682-5773/8684-4914/8647-7487 E-mail Address: [email protected]

218

Physical Science Catalyst

219

Introductory Message

For the facilitator:

Welcome to the Physical Science Grade 11 Alternative Delivery Mode (ADM) Module on Catalyst!

In addition to the material in the main text, you will also see this box in the body of the module:

Notes to the Teacher This contains helpful tips or strategies that will help you in guiding the learners.

220

For the learner:

Welcome to the Physical Science 11 Alternative Delivery Mode (ADM) Module on Catalyst!

This module has the following parts and corresponding icons:

What I Need to Know This will give you an idea of the skills or

competencies you are expected to learn in the module.

What I Know This part includes an activity that aims to

check what you already know about the lesson to take. If you get all the answers correct (100%), you may decide to skip this module.

What’s In This is a brief drill or review to help you link

the current lesson with the previous one.

What’s New In this portion, the new lesson will be

introduced to you in various ways such as a story, a song, a poem, a problem opener, an activity or a situation.

What is It This section provides a brief discussion of the

lesson. This aims to help you discover and understand new concepts and skills.

What’s More This comprises activities for independent

practice to solidify your understanding and skills of the topic. You may check the answers to the exercises using the Answer Key at the end of the module.

What I Have Learned This includes questions or blank

sentence/paragraph to be filled into process what you learned from the lesson.

What I Can Do This section provides an activity which will

help you transfer your new knowledge or skill into real life situations or concerns.

221

Assessment This is a task which aims to evaluate your

level of mastery in achieving the learning competency.

Additional Activities In this portion, another activity will be given

to you to enrich your knowledge or skill of the lesson learned. This also tends retention of learned concepts.

Answer Key This contains answers to all activities in the

module.

At the end of this module you will also find:

References This is a list of all sources used in developing this module.

The following are some reminders in using this module:

We hope that through this material, you will experience meaningful learning and gain deep understanding of the relevant competencies. You can do it!

222

Week

What I Need to Know

This module was designed and written with you in mind. It is here to help you to define catalyst and describe how it affects reaction rate. The scope of this module permits it to be used in many different learning situations. The language used recognizes the diverse vocabulary level of students. The lessons are arranged to follow the standard sequence of the course. But the order in which you read them can be changed to correspond with the textbook you are now using.

The module contains discussion about catalyst as one of the factors affecting the reaction rate.

After going through this module, you are expected to: 1. describe the concept of catalyst; 2. present catalyst as an effective means of affecting the reaction rate; and 3. realize the importance of catalyst and how it affects your life.

223

What I Know

Directions: Modified TRUE or FALSE. On the space at the left, write TRUE if the statement is true. If the statement is false, change the italicized word to make it correct.

______1. A catalyst is a substance that can be added to a reaction to increase the reaction rate without getting consumed in the process.

______2. Heat is not a catalyst since it can’t be taken out of the reaction in the same amount it was inputted into the reaction.

______3. Catalysts increase the rates of chemical reactions by raising the activation energy of the reactions.

______4. Collisions only result in a reaction if the particles collide with a certain maximum energy called the activation energy of the reaction.

______5. A chemical reaction may be energetically favorable (i.e. exothermic), and so if the activation barrier is high (i.e. the activation energy is high), the reaction rate may be extremely slow.

______6. Decreasing the concentration of reactants increases the collision frequency between reacting particles.

______7. Increasing the concentration of a substance increases the kinetic energy of the particles that make up the substance.

______8. Raising the temperature of a reaction increases the rate of the reaction by increasing the energy of the collisions between reacting particles.

______9. Lowering the surface area of a reactant increases the rate of the reaction.

224

______10. Catalysts permit reactions to proceed along a higher energy path.

______11. Smaller particle size allows for a larger surface area to be exposed for the reaction.

______12. Temperature is the measure of how much area of an object is exposed.

______13. Grains of sugar have a greater surface area than a solid cube of sugar of the same mass, and therefore will dissolve quicker in water.

______14. Decreasing the temperature causes the particles (atoms or molecules) of the reactants to move more quickly so that they collide with each other more frequently and with more energy.

______15. Catalyst describes the idea that atoms, ions, and molecules must collide in order to react.

225

Lesson 1 Catalyst

Reaction rates generally increase with increasing reactant concentration, increasing temperature, and the addition of a catalyst. Physical properties such as high solubility also increase reaction rates. Solvent polarity can either increase or decrease the rate of reaction, but increasing solvent viscosity generally decreases reaction rates.

Although a balanced chemical equation for a reaction describes the quantitative relationships between the amounts of reactants present and the amounts of products that can be formed, it gives us no information about whether or how fast a given reaction will occur. This information is obtained by studying the chemical kinetics of a reaction, which depend on various factors: reactant concentrations, temperature, physical states and surface areas of reactants, and solvent and catalyst properties if either are present. By studying the kinetics of a reaction, chemists gain insights into how to control reaction conditions to achieve a desired outcome.

Figure 1: The figure shows how temperature affects the rate of reaction as it increases the kinetic energy of the molecules, thus increasing their chances of overcoming the energy barriers they need to have the reaction go to completion.

226

What’s In

Word Search: Search and encircle to unlock the pool of words in the box then use them by filling in the blanks to complete the passage. Factors Affecting the Rate of Reaction

A C T I V A T I O N E N E R G Y M G B W D N B M L Y L M A W D M T M Q Y R T A C P A R T I C L E S I Z E Z E N S I T A S I E A R T V E N D T T N D Y T R N R R M Q A B N D Q G R M Z A L L E G E Y P T M O V K Z E V C Y C A C J M S M E X I D C L I O V Y M T T L O T P P R T O I D N T D B L E I A T Q M I E A C M T H Y O Y L R S V C O N C E N T R A T I O N D B B P A N Z E L I O U A B L P E L D P Q L I K R D X Y H R I T M P Z R W M T R I P Y O K T M E I X U N S N M B N R

Concentration Activation energy Catalyst Temperature

Particle Size Enzymes

Increasing the ______of a system increases the average kinetic energy of its constituent particles. As the average kinetic energy increases, the particles move faster and collide more frequently per unit time and possess greater energy when they collide. When the ______of all the reactants increases, more molecules or ions interact to form new compounds, and the rate of reaction increases. When solids and liquids react, increasing the surface area of the solid will increase the reaction rate. A decrease in ______causes an increase in the solid’s total surface area. Collisions only result in a reaction if the particles collide with a certain minimum energy called the ______for the reaction. The position of activation energy can be determined on a Maxwell-Boltzmann distribution. To increase the rate of a reaction, the number of successful collisions must be increased. One possible way of doing this is to provide an alternative way for the reaction to happen which has a lower activation energy. Adding ______has this effect on activation energy. It provides an alternative route for the reaction with a lower activation energy. Catalysts are everywhere! Many biochemical processes, such as the oxidation of glucose, are heavily dependent on ______, proteins that behave as catalysts.

227

Notes to the Teacher

A Word of Caution!

Care must be taken when discussing how a catalyst operates. A catalyst provides an alternative route for the reaction with a lower activation energy. It does not "lower the activation energy of the reaction". There is a subtle difference between the two statements that is easily illustrated with a simple analogy. Suppose there is a mountain between two valleys such that the only way for people to get from one valley to the other is over the mountain. Only the most active people will manage to get from one valley to the other.

Now suppose a tunnel is cut through the mountain. Many more people will now manage to get from one valley to the other by this easier route. It could be said that the tunnel route has a lower activation energy than going over the mountain, but the mountain itself is not lowered. The tunnel has provided an alternative route but has not lowered the original one. The original mountain is still there, and some people still choose to climb it. In chemical terms, if particles collide with enough energy, they can still react in exactly the same way as if the catalyst was not there; it is simply that the majority of particles will react via the easier catalyzed route.

228

What’s New

Excellent! You are good in analyzing information. As a reward, I will share a story with you.

Wow, I do love hearing

stories. Can’t wait any longer Professor X.

I am more than glad and happy hearing that from you. I’ll just get my book and read it for you.

Maria and Pedro met in Mr. Fallarna’s first grade class. They were friends all through

grade school, high school, and college. Their friends and family members all thought that they should date, but they never did, and the people around them began to get impatient. Finally, their friends Sarah and Juan took the matter into their own hands. Sarah asked Maria to go a concert with her, and Juan asked Pedro to go to the same concert with him. At the last minute, Sarah and Juan cancelled, leaving Maria and Pedro to attend the concert together. They began dating and later got married.

229

What a happy ending! They are very lucky for having friends like Sarah and Juan. They act like catalyst in their relationship. In chemistry, it is any substance that increases the rate of reaction without itself being consumed. One good example are enzymes that are naturally occurring catalyst responsible for essential biochemical reactions.

So, apples go brown when their flesh reacts with air. In the pictures below, which apple will go brown the quickest? Why?

______.

A B C D

Figure 2: Apple set ups in different sizes.

What is It

Key Terms

 Activation energy: the minimum energy required for a reaction to occur.  Catalysis: the increase in the rate of a chemical reaction by lowering its activation energy.  Transition state: an intermediate state during a chemical reaction that has a higher energy than the reactants or the products.  Maxwell-Boltzmann Distribution: a probability distribution used for describing the speeds of various particles within a stationary container at a specific temperature. The distribution is often represented with a graph, with the y-axis defined as the number of molecules and the x-axis defined as the speed.

230

The Effect of a Catalyst on Rate of Reaction

This part explains how adding a catalyst affects the rate of reaction. It assumes familiarity with basic concepts in the collision theory of reaction rates, and with the Maxwell-Boltzmann distribution of molecular energies in a gas. A catalyst is a substance which speeds up a reaction, but is chemically unchanged at its end. When the reaction has finished, the mass of catalyst is the same as at the beginning. Several examples of catalyzed reactions and their respective catalysts are given below:

Reaction Catalyst Decomposition of hydrogen peroxide manganese(IV) oxide, MnO2 Nitration of benzene concentrated sulfuric acid Manufacture of ammonia by the Haber iron Process Conversion of SO2 into SO3 during the vanadium(V) oxide, V2O5 Contact Process to make sulfuric acid Hydrogenation of a C=C double bond nickel

The Importance of Activation Energy

Collisions only result in a reaction if the particles collide with a certain minimum energy called the activation energy for the reaction. The position of activation energy can be determined on a Maxwell-Boltzmann distribution:

The number of particles represented by Only the number of particles represented the area under this part of the curve by the area under this part of the curve don’t have enough energy to react. have high enough energies to react.

Number of particles

Activation energy Only those particles represented by the area to the right of the activation energy will react when they collide. The majority do not have enough energy, and will simply bounce apart.

231

To increase the rate of a reaction, the number of successful collisions must be increased. One possible way of doing this is to provide an alternative way for the reaction to happen which has a lower activation energy. In other words, to move the activation energy to the left on the graph:

Now all these extra particles have enough energyOriginally, to only the Number of react as well.number of particles particles represented by the area under this part of the curve had high enough energies to react. particles which don’t have enough energy to react

Energy

new activation energy original activation energy

Adding a catalyst has this effect on activation energy. A catalyst provides an alternative route for the reaction with a lower activation energy. This is illustrated on the following energy profile:

232

What’s More

Catalyst is one of the factors that can affect the rate of reaction along with concentration, temperature, and size of the particles as discussed on the previous module.

The video links below show a simple experiment and a discussion on how catalyst react with substances, hence affecting its rate.

Answer the guide questions below after watching each video.

Link 1: https://www.youtube.com/watch?v=m_9bpZep1QM&t=41s Link 2: https://www.youtube.com/watch?v=5JpGbhAP3ZE

Link 1: Guide Questions

1. What is a catalyst? 2. How does catalyst work? 3. In the video, where are catalysts used in everyday life?

Link 2: Guide Questions

1. What substance in the experiment contains catalyst that helps in the reaction? 2. What happens when the yeast is added to the hydrogen peroxide? 3. What enzyme catalyst was produced by the substance? 4. How would you differentiate catalyst from temperature as a factor affecting the rate of reaction? 5. What is the significance of putting flame on the solution in the experiment?

233

What I Have Learned

Complete the group of words to form relevant ideas about the lesson.

 A catalyst is…

 An enzyme…

 Activation energy is related to rate of reaction because…

 Without catalyst, life is…

What I Can Do

Just like catalysts explained in science, there are also some factors that may affect us to grow or hinder our rate of success.

It may include your family, friends, opportunities, or your personality. Will you share it with me? Who/What are the influencers in your life? Write it on your journal.

______My Journal ______

234

Assessment

Directions: Encircle the letter of the correct answer.

1. How does a catalyst work in speeding up a reaction? a. It lowers the activation energy. b. It provides more energy. c. It creates more reactants. d. It increases the temperature.

2. The minimum amount of energy needed for colliding particles to react is called the a. chemical energy c. kinetic energy b. activation energy d. potential energy

3. A substance that increases the rate of a reaction without being used up during the reaction is called a a. catalyst c. product b. reactant d. solute

4. Catalysts permit reactions to proceed along a ______energy path. a. higher c. restricted b. lower d. stabler

5. What is an enzyme? a. An inorganic substance added to food for better digestion. b. An organic molecule that dissolves nutrients in the body. c. A biomolecule that releases energy during chemical reactions. d. A biomolecule that serves as catalyst in biological system.

6. Which of the following explains why product molecules are not formed despite despite numerous collisions? Choose all that apply. a. Number of collisions c. Orientation b. Activation energy d. Energy released by reaction

7. How is catalyst different from a reactant? a. Adding more catalyst speeds up the rate of reaction. b. Adding more catalyst slows down the rate of reaction. c. The catalyst is not used up in the reaction. d. The catalyst increases the activation energy of the reaction.

8. Which of the following increases the speed of reaction? Choose all that apply. a. Raising the temperature. c. Adding a catalyst. b. Adding more reactants. d. Adding more products.

235

9. The rate of a chemical reaction is NOT affected by which of the following? a. Temperature c. Concentration b. Particle size d. None of these

10. Products will form faster if______. a. the particle size of the reactants are larger. b. temperature is decreased. c. the concentration of the reactants are increased. d. the reaction is not stirred.

11. Choose two options that will INCREASE the rate of reaction. a. Reducing heat c. Adding catalyst b. Adding heat d. Removing catalyst

12. Which of the following will lower the rate of reaction? a. Adding an enzyme to the reaction. b. Decreasing the temperature from 40oC to 10oC. c. Breaking a chunk of calcium up into smaller pieces. d. Increasing the amount of solute dissolved in solution.

13. Smaller particle size results to a ______surface area to be exposed for the reaction. a. larger c. smaller b. regular d. spherical

14. Which of the following is NOT a characteristic of a catalyst? a. It participates in the reaction. c. It enhances the equilibrium rate. b. It activates equilibrium. d. It initializes the reaction.

15. What must happen before a chemical reaction can begin? a. The activation energy must be exceeded. b. The activation energy must be reached. c. The concentration of reactant molecules must be reduced. d. The concentrations of products and reactants must be equal.

Additional Activities

In your most creative way, how will you define catalyst and describe how it affects reaction rate?

It can be through a song, a role play (experiment), poem, poster, or interpretative dance. A 5-minute-performance will be evaluated using a common rubric to be given by the teacher.

236

Answer Key

enzymes

Catalyst 5.

energy Activation

size Particle 3.

Concentration

Temperature 1.

Passage. theory Collision 15.

Increasing 14.

TRUE 13.

area Surface 12.

TRUE 11.

Lower

10. TRUE 9.

TRUE 8.

TRUE 7.

Increasing 6.

TRUE 5.

Minimum 4.

Lowering 3.

TRUE 2.

TRUE

1. Search Words

Know I What In What’s

browning.

is enzymatic enzymatic is

air to reacts enzyme

place here when an an when here place

oxygen.

reaction that takes takes that reaction

To test if combustion is possible due to the presence of of presence the to due possible is combustion if test To 5.

the of process The reaction. the during consumed not is It 4.

area, hence letter D. D. letter hence area,

Catalase 3.

smallest surface surface smallest

oxygen. of release the of result a as bubbles produces It 2.

the with one the yeast. the is It 1.

reaction, it will be be will it reaction,

affecting the rate of of rate the affecting 2: Link

the factors factors the applying converters. catalytic

than A. And by by And A. than Used in the haber process, contact process and and process contact process, haber the in Used 3.

to go brown slower slower brown go to energy. activation lower a has This occur.

makes apple B,C,D B,C,D apple makes provides an alternative pathway for the reaction to to reaction the for pathway alternative an provides It 2.

reacts to air, it it air, to reacts reaction.

Since apple’s flesh flesh apple’s Since It speeds up the reaction but not used up in the the in up used not but reaction the up speeds It 1.

brown the quickest. quickest. the brown

Apple D will go go will D Apple 1. 1: Link

New What’s More What's

237

Answer Key

. vary may Answers 4.

barrier. energy activation

the of top the reached have they once

B 15.

reaction the complete only can molecules

A 14.

because is This be. will reaction chemical A 13. higher the activation energy, the slower the the slower the energy, activation the higher

B 12. losely related to its rate. Specifically, the the Specifically, rate. its to related losely c is

C and B 11.

The activation energy of a chemical reaction reaction chemical a of energy activation The 3.

C 10.

cells. within place take

D 9.

that reactions chemical the of all virtually of

C and A,B, 8. proteins) that significantly speed up the rate rate the up speed significantly that proteins)

C 7. Enzymes are biological molecules (typically (typically molecules biological are Enzymes 2.

D and C 6.

catalyze. or

D 5. it has been used to speed up, up, speed to used been has it

reaction the of

B 4.

end the at unchanged chemically recovered

A 3.

be can catalyst a hence reaction; the B 2. chemical reaction, but is not consumed by by consumed not is but reaction, chemical

A 1. A catalyst is a substance that speeds up a a up speeds that substance a is catalyst A 1.

Assessment

Learned Have I What

238

References

Boone, Silvester. “Slideplayer”. Rates of Reaction. https://slideplayer.com/slide/8382648/ (accessed May 23, 2020)

“Chemistry Libretexts”. Factors that Affect Reaction Rates. https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemist ry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chem istry)/Kinetics/Reaction_Rates/Factors_That_Affect_Reaction_Rates (accessed May 23, 2020) Clark, Jim. “Chemistry Libretexts”. The Effect of a Catalyst on Rate of Reaction. https://chem.libretexts.org/Bookshelves/Inorganic_Chemistry/Modules_an d_Websites_(Inorganic_Chemistry)/Catalysis/The_Effect_of_a_Catalyst_on_R ate_of_Reaction (accessed May 23, 2020)

“Khan Academy”. Types of Catalysts. https://www.khanacademy.org/science/chemistry/chem- kinetics/arrhenius-equation/a/types-of-catalysts (accessed May 23, 2020)

239

For inquiries or feedback, please write or call:

Department of Education - Bureau of Learning Resources (DepEd-BLR)

Ground Floor, Bonifacio Bldg., DepEd Complex Meralco Avenue, Pasig City, Philippines 1600

Telefax: (632) 8634-1072; 8634-1054; 8631-4985

Email Address: [email protected] * [email protected]

240

Physical Science

241

Physical Science Limiting Reactants and the Amount of Products Formed First Edition 2020

Published by the Department of Education Secretary: Leonor Magtolis Briones Undersecretary: Diosdado M. San Antonio

Development Team of the Module

Writer: Francis Darril A. Albo Editors: Robert G. Yumul Angelica J. Macaraeg Reviewer: Ramonito O. Elumbaring Illustrator: Francis Victor A. Medrano Layout Artist: Mary Grace L. Asa Pamela A. Lalusin Management Team: Wilfredo E. Cabral, Regional Director Job S. Zape Jr., CLMD Chief Elaine T. Balaogan, Regional ADM Coordinator Susan DL Oribiana, Schools Division Superintendent Lorna R. Medrano, CID Chief Edita T. Olan, EPS-in-Charge, LRMS

Department of Education – Region IV-A CALABARZON

Office Address: Gate 2 Karangalan Village, Barangay San Isidro Cainta, Rizal 1800 Telefax: 02-8682-5773/8684-4914/8647-7487 E-mail Address: [email protected]

242

Physical Science Limiting Reactants and the Amount of Products Formed

243

Introductory Message

For the facilitator:

Welcome to the Physical Science Grade 11 Alternative Delivery Mode (ADM) Module on Limiting Reactants and the Amount of Products Formed!

In addition to the material in the main text, you will also see this box in the body of the module:

Notes to the Teacher This contains helpful tips or strategies that will help you in guiding the learners.

As a facilitator you are expected to orient the learners on how to use this module. You also need to keep track of the learners’ progress while allowing them to manage their own learning. Furthermore, you are expected to encourage and assist the learners as they do the tasks included in the module.

244

For the learner:

Welcome to the Physical Science Grade 11 Alternative Delivery Mode (ADM) Module on Limiting Reactants and the Amount of Products Formed!

This module has the following parts and corresponding icons:

What I Need to Know This will give you an idea of the skills or

competencies you are expected to learn in the module.

What I Know This part includes an activity that aims to

check what you already know about the lesson to take. If you get all the answers correct (100%), you may decide to skip this module.

What’s In This is a brief drill or review to help you link

the current lesson with the previous one.

What’s New In this portion, the new lesson will be

introduced to you in various ways such as a story, a song, a poem, a problem opener, an activity or a situation.

What is It This section provides a brief discussion of the

lesson. This aims to help you discover and understand new concepts and skills.

What’s More This comprises activities for independent

practice to solidify your understanding and skills of the topic. You may check the answers to the exercises using the Answer Key at the end of the module.

What I Have Learned This includes questions or blank

sentence/paragraph to be filled in to process what you learned from the lesson.

What I Can Do This section provides an activity which will

help you transfer your new knowledge or skill into real life situations or concerns.

245

Assessment This is a task which aims to evaluate your

level of mastery in achieving the learning competency.

Additional Activities In this portion, another activity will be given

to you to enrich your knowledge or skill of the lesson learned. This also tends retention of learned concepts.

Answer Key This contains answers to all activities in the

module.

At the end of this module you will also find:

References This is a list of all sources used in developing this module.

The following are some reminders in using this module:

We hope that through this material, you will experience meaningful learning and gain deep understanding of the relevant competencies. You can do it!

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Week

What I Need to Know

This module was designed and written with you in mind. It is here to help you to use the stoichiometric calculation to determine excess and limiting reactants in a chemical reaction. Also, it helps you to understand on how to perform calculation in product formation. The scope of this module permits it to be used in many different learning situations. The language used recognizes the diverse vocabulary level of students. The lessons are arranged to follow the standard sequence of the course. But the order in which you read them can be changed to correspond with the textbook you are now using.

After going through this module, you are expected to: 1. Use stoichiometric calculation to determine excess and limiting reactants in a chemical reaction and explain why. 2. Calculate theoretical yields of products formed in reactions that involve limiting reagents.

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What I Know

Directions: Analyze and answer the reaction and problem below.

1. Write the equation for the reaction of iron (III) phosphate with sodium sulfate to make iron (III) sulfate and sodium sulfate. 2. If I perform this reaction with 25 grams of iron (III) phosphate and an excess of sodium sulfate, how many grams of iron (III) phosphate can I make? 3. If 18.5 grams of iron (III) phosphate are actually made when I do this reaction, what is my percent yield? 4. Is the answer from problem #3 reasonable? Explain. 5. If I do this reaction with 15 grams of sodium sulfate and get a 65.0% yield, how many grams of sodium phosphate will I make?

6. In the equation Mg + O2(g)  MgO, how many molecules of Mg on the reactant side do we need to make our equation balance? a. 2 c. 3 b. b. 1 d. 4

7. Use the following BALANCED equation: 2C2H6 + 7O2 4CO2 + 6H2O

If 15 g of C2H6 react with 45 g of O2, how many grams of water will be produced?

a. 27 g H2O c. 22 g H2O

b. 28 g H2O d. 23 g H2O

8. What is the limiting reactant?

a. O2 c. H2O

b. b. C2H6 d. CO2

9. What is the excess reactant?

a. O2 c. H2O

b. b. C2H6 d. CO2

10. Consider the following reaction: 2Al + 6HBr 2AlBr3 + 3H2

When 86.9 grams of Al reacts with 401 grams of HBr, how many H2 are formed? a. 5.01 g c. 8.01 g b. 7.01 g d. 10.01 g

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11. What is the limiting reactant? a. Al c. HBr

b. AlBr3 d. H2

12. For the excess reactants, how many grams are left over at the end of the reaction? a. 47.4 g c. 44.3 g b. 42.3 g d. 48.4 g

13. The reactant which was not used up after the completion of the chemical reaction. a. Reactants b. Limiting Reagents b. Solute d. Excess Reagents

14. It deals with the process that involves rearrangement of the molecular or ionic structure of a substance to form a new substance or product. a. Chemical Equilibrium c. Chemical Reaction b. Chemical Kinetics d. Stoichiometry

15. Which of the following is the correct sequence of a chemical equation? a. Reactant  Product c. Reactant + Product b. Catalyst  Product d. Product + Reactant

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Lesson Physical Sciences: Limiting Reactants and the Amount 1 of Products Formed

Chemical equations give the ideal stoichiometric relationship of reactants and products. However, sometimes the amount of reactants used are not mixed in exact or proper ratio. Thus, some reactants will be in excess and others will be completely used up. In a chemical reaction, reactants that are not used up when the reaction is finished are called excess reagents. The reagent that is completely used up is called the limiting reagent, because its quantity limits the amount of products formed.

Fig 1

Figure shows the parts of chemical reaction. We have two elements in the reactant side that will undergo chemical reaction to produce a product: A + B → AB. An example of a synthesis reaction is the combination of two molecules of H and two molecules of Oxygen gas to produce one molecule of water.

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What’s In

Chemical reaction deals with the process that involves rearrangement of the molecular or ionic structure of a substance, as opposed to a change in physical form or a nuclear reaction.

A chemical equation shows the starting compound(s)—the reactants—on the left and the final compound(s)—the products—on the right, separated by an arrow. In a balanced chemical equation, the numbers of atoms of each element and the total charge are the same on both sides of the equation.

For example:

The figure shows the combustion of methane, CH4 (a hydrocarbon) that produces carbon dioxide and water.

Notes to the Teacher Let the student explore and learn the concept of stoichiometry and apply it on how to identify the limiting and excess reactant. Also let them how to apply their knowledge in basic mathematics in order to find the value of product yields.

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What’s New

Key Terms  Stoichiometry is a branch of chemistry that establishes mole and mass relationships between reactants and/or products in a chemical reaction to determine desired quantitative data.  Excess reagent is a reactant that is not used up when the reaction is finished.  Limiting reagent is a reagent that is completely used up in a chemical reaction. In this activity, you will be introduced to simple stoichiometry. Stoichiometry includes calculations that allow us to find the amounts of chemicals involved in each reaction.

In stoichiometry, you must always start with a balanced equation. We will use the following balanced recipe (equation):

2 Gc + 1 M 1 Sm Where: Gc = graham cracker M = marshmallow Sm = s’more

1. Notice that to make this recipe you have three pieces (reactant) to the left of the arrow and one piece (product) to the right. This is supposed to represent a balanced equation, so how can 3 = 1?

It’s because the pieces combine to form one whole. This would represent a synthesis reaction.

2. If each student is to make one s’more, and I have 20 students, how much of each ingredient will I need? Explain your logic – using a chemical equation.

2 Gc + 1 M  1 Sm (Use the ratio of the coefficients) 40 20 20

Let's look at a simplified view of the s'mores example. She starts out with six graham crackers and four marshmallows.

How many marshmallows would be needed if all six of the graham crackers were used? Which of the two ingredients do you think will be used up first?

12 Which ingredient will have excess? 3 9

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Let’s ask Professor F: Hi there, let me help you! The correct answer is THREE. WHY? The six graham crackers would require three marshmallows to make three s'mores.

Which of the two ingredients run out first? Answer: Graham

Since she has four marshmallows (a greater supply than what is needed), the graham crackers will limit the number of s'mores she can make.

Alternatively, you could look at the number of graham crackers that would be needed.

Suppose wanted to make four s’mores using the available ingredients earlier, how many graham crackers would I need if I have four marshmallows? 4 8 1 Great, the four marshmallows would require eight graham crackers to make four s'mores.

Since there are only six graham crackers (a supply less than what is needed), the graham crackers will limit the number of s'mores she can make.

You can see that the conclusion reached was the same regardless of the ingredient (or reactant) chosen.

Let’s Try This!

We have five hot dogs and four hot dog buns. How many complete hot dogs sandwiches can we make?

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What is It

PROBLEM SOLVING TIP:

The first and most important step for any stoichiometric calculation is to start with a balanced reaction. Since our calculations use ratios based on the stoichiometric coefficients, our answers will be incorrect if the stoichiometric coefficients are not right.

Here are the steps on how to balance a chemical equation:

1. Write down your given equation. For this example, you will use:

C3H8 + O2 --> H2O + CO2 This reaction occurs when propane (C3H8) is burned in the presence of oxygen to produce water and carbon dioxide.

2. Write down the number of atoms per element. Do this for each side of the equation. Look at the subscripts next to each atom to find the number of atoms in the equation. When writing it out, it's a good idea to connect it back to the original equation, noting how each element appears. Reactant Product Carbon (C) 3 1 Oxygen (O) 2 3 Hydrogen (H) 8 2

3. Save hydrogen and oxygen for last, as they are often on both sides. Hydrogen and oxygen are both common in molecules, so it's likely that you'll have them on both sides of your equation. It's best to balance them last.

 You'll need to recount your atoms before balancing the hydrogen and oxygen, as you'll likely need to use coefficients to balance the other atoms in the equation.

4. Start with single elements. If you have more than one element left to balance, select the element that appears in only a single molecule of reactants and in only a single molecule of products. This means that you will need to balance the carbon atoms first.

5. Use a coefficient to balance the single carbon atom. Add a coefficient to the single carbon atom on the right of the equation to balance it with the 3 carbon atoms on the left of the equation.

C3H8 + O2 --> H2O + 3CO2

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The coefficient 3 in front of carbon on the right side indicates 3 carbon atoms just as the subscript 3 on the left side indicates 3 carbon atoms.

In a chemical equation, you can change coefficients, but you must never alter the subscripts.

6. Balance the hydrogen atoms next. Since you have balanced all atoms besides the hydrogen and oxygen, you can address the hydrogen atoms. You have eight on the left side. So you'll need eight on the right side. Use a coefficient to achieve this.

 C3H8 + O2 -->4H2O + 3CO2  On the right side, you now added four as the coefficient because the subscript showed that you already had two hydrogen atoms.  When you multiply the coefficient four times by the subscript two, you end up with eight.

 The other six atoms of oxygen come from 3CO2. (3x2=6 atoms of oxygen + the other 4=10)

7. Balance the oxygen atoms. Remember to account for the coefficients that you've used to balance out the other atoms. Because you've added coefficients to the molecules on the right side of the equation, the number of oxygen atoms has changed. You now have four oxygen atoms in the water molecules and 6 oxygen atoms in the carbon dioxide molecules. That makes a total of ten oxygen atoms.  Add a coefficient of five to the oxygen molecule on the left side of the equation. You now have 10 oxygen atoms on each side.

 C3H8 + 5O2 -->4H2O + 3CO2

Example 1: Finding the limiting reagent

For the following reaction, what is the limiting reagent if we start with 2.80g of Al (Aluminum) and 4.25g of Cl (Chlorine)?

2Al(s)+3Cl2(g)→2AlCl3(s)

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First, let’s check if our reaction is balanced: we have two Al atoms and six Cl atoms on both sides of the arrow, so we are good to go! In this problem, we know the mass of both reactants, and we would like to know which one will get used up first. In the first step, we will convert everything to moles, and then we will use the stoichiometric ratio from the balanced reaction to find the limiting reagent.

Step 1: Convert amounts (grams) to moles.

We can convert the masses of Al and Cl2 to moles using molecular weights:

(Convert g Al to mol Al)

(Convert g Cl2to mol Cl2) Step 2: Find the limiting reagent using the stoichiometric ratio.

Now that our known quantities are in moles, there are multiple ways to find the limiting reagent. We will show three methods here. They all give the same answer, so you can choose your favorite. All three methods use the stoichiometric ratio in slightly different ways.

METHOD 1: The first method is to calculate the actual molar ratio of the reactants, and then compare the actual ratio to the stoichiometric ratio from the balanced reaction.

The actual ratio tells us that we have 1.74 mol of Al for

every 1 mol of Cl2. In comparison, the stoichiometric ratio from our balanced reaction is below:

This means we need at least 0.67 moles of Al for every mole of Cl2. Since our actual ratio is greater than our stoichiometric ratio, we have more Al than we need to react with each mole of Cl2. Therefore, Cl2is our limiting reagent and Al is in excess.

METHOD 2: A more guess-and-check way you can figure out the limiting reactant is by choosing one of the reactants—it doesn’t matter which one—and pretending that it is the limiting reagent. We can then calculate the moles of the other reagent needed based on the moles of our pretend

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limiting reagent. For example, if we pretend that Al is the limiting reagent, we would calculate the required amount of Cl2 as follows:

Based on this calculation, we would need 1.56x10-1 mol of Cl2 if Al is actually the limiting reagent. Since we have -2 -1 5.99 x10 mol Cl2which is less than 1.56x10 mol of Cl2

our calculation tells us that we would run out of Cl2 before we fully reacted all of the Al. Therefore, 1.56x10-1 mol of Cl2is our limiting reagent.

METHOD 3: The third method uses the concept of a mole of reaction, which is abbreviated as mol-rxn. One mole of reaction is defined as occurring when the number of moles given by the coefficients in your balanced equation react. That definition can sound rather confusing, but the idea is hopefully more clear in the context of our example. In the current reaction, we would say that one mole of reaction is when two moles of Al react with three moles

Cl2 to produce two moles AlCl3 which we can also write as:

1mol-rxn=2mol Al=3mol Cl2=2mol AlCl3 We can use the above relationship to set up ratios to convert the moles of each reactant to moles of reaction:

The more moles of reaction you have, the more times the reaction can occur. Therefore, the reactant with fewer moles of reaction is the limiting reagent since the reaction can be carried out fewer times with that reactant. We see that this method also Cl2 is our limiting reagent because it makes 2.00×10−2mol-rxn, which is less than 5.20×10−2mol-rxn, from Al.

Example 2: Calculating theoretical yield Now that we know the limiting reagent, we can use that information to answer the following question:

What is the theoretical yield of AlCl3 that the reaction can produce when we start with 4.25 g of Cl2, our limiting reagent? We can use the moles of limiting reagent plus the stoichiometric ratios from our balanced reaction to calculate the theoretical yield. The coefficients from the

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balanced reaction tell us that for every three mol of Cl2we should make two mol of

AlCl3. Therefore, the theoretical yield, in moles, is:

The theoretical yield is usually expected to have units of mass, so we can convert moles of AlCl3to grams using the molecular weight:

Percent Yield The theoretical yield is the maximum amount of product you would expect from a reaction based on the amount of limiting reagent. In practice, however, chemists don’t always obtain the maximum yield for many reasons. When running a reaction in the lab, loss of product often occurs during purification or isolation steps. You might even decide it is worth losing 10% of your product during an extra purification step because it is more important to have extremely pure product—as opposed to having a larger amount of less pure product.

Oh no, a cat-burglar stole a hot dog bun! That makes the actual yield three complete hot dogs. If our theoretical yield was four complete hot dogs, what is our percent yield?

Source: https://www.khanacademy.org/s cience/chemistry/chemical- reactions-stoichiome/limiting- reagent-stoichiometry/a/limiting- reagents-and-percent-yield

Despite how nice and tidy a balanced reaction appears, reactants can also react in unexpected and undesirable ways such as doing an entirely different reaction—sometimes called a side reaction—to give products that we don't want. Your actual yield may change based on factors such as the relative stability of reactants and products, the purity of the chemicals used, or the humidity on a given day. In some cases, you might be left with all starting materials and no products after your reaction. The possibilities are endless!

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Since chemists know that the actual yield might be less than the theoretical yield, we report the actual yield using percent yield, which tells us what percentage of the theoretical yield we obtained. This ratio can be very valuable to other people who might try your reaction. The percent yield is determined using the following equation:

Since percent yield is a percentage, you would normally expect to have a percent yield between zero and 100. If your percent yield is greater than 100, that probably means you calculated or measured something incorrectly.

Example 3. Calculating theoretical and percent yield

For example, the decomposition of magnesium carbonate (MgCO3) forms 15 grams of magnesium oxide (MgO) in an experiment. The theoretical yield is known to be 19 grams. What is the percent yield of magnesium oxide (MgO)?

MgCO3 MgO CO2 Mg =1x24.31 g/mol Mg =1x24.31 g/mol C = 1x12.01 g/mol C = 1x12.01 g/mol O=1x16.00 g/mol O=2x16.00 g/mol O=3x16.00 g/mol MgCO3=84.32 g/mol MgO = 40.31 g/mol CO2=44.01 g/mol MgCO3 → MgO + CO2 What is the percent yield of the reaction?

First, we check to see if the reaction is balanced. It looks like we have equal numbers of all atoms on both sides, so now we can move on to calculating the theoretical yield.

The calculation is simple if you know the actual and theoretical yields. All you need is substitute the values into the formula: percent yield = 15 g / 19 g x 100%

percent yield = 79%

Usually, you have to calculate the theoretical yield based on the balanced equation. In this equation, the reactant and the product have a 1:1 mole ratio, so if you know the amount of reactant, you know the theoretical yield is the same value in moles (not grams!). You take the number of grams of reactant you have, convert it to moles, and then use this number of moles to find out how many grams of product to expect.

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What’s More

Activity 1. Limiting Reactants Calculation

Directions: Answer the following questions below. Use three significant figures in your computation and final answer.

1. Consider the following reaction: 2Al + 6HBr  2 AlBr3 ------+3H2 a. When 3.22 moles of Al react with 4.96 moles of HBr, how many moles

of H2 are formed? b. What is the limiting reactant?

2. Consider the following reaction: 3Si + 2N2 Si3N4

a. When 21.44 moles of Si react with 17.62 moles of N2, how many moles

of Si3N4 are formed? b. What is the limiting reactant?

What I Have Learned

The limiting reagent is the reactant that gets used up first during the reaction and also determines how much product can be made. We can find the limiting reagent using the stoichiometric ratios from the balanced chemical reaction along with one of the many nifty methods in Example 1.

Once we know the limiting reagent, we can calculate the maximum amount of product possible, which is called the theoretical yield. Since the actual amount of product is often less than the theoretical yield, chemists also calculate the percent yield using the ratio between the experimental and theoretical yield.

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What I Can Do

Lab: Limiting Reactants Activity—Datasheet Do the activity below using your knowledge about limiting reactant.

One (Gu) Guava reacts with four (Je) Jelly to form a (GuJe) Guava Jelly according to the following BALANCED equation.

1 Gu + 4 Je 1 GuJe

Question No. 1 a. How many Guava Jelly (GuJe) can be formed using 5 Guava and 23 Jelly? b. What is the limiting reactant? c. What is the excess reactant? d. How much is left over? e. Use the balanced equation to answer the following question. One Guava has a mass of 2.0 grams and one Jelly has a mass of 1.5 g. How many Guava Jelly can be made with 12.5 grams of Guava and 15.0 grams of Jelly?

Two PANSIT reacts with six SILING LABUYO to form a HOT Pansit according to the following BALANCED

equation.

2P + 6 SB • 1 HP

a. How many Hot Pansit can be formed using 10 Pansit and 24 Siling Labuyo? b. What is the limiting reactant? c. What is the excess reactant? d. How much is left over? e. Use the balanced equation to answer the following question. One Pansit has a mass of 5.0 grams and one Siling Labuyo has a mass of 1.0 gram. How many Hot Pansit can be made from 40.0 grams of Pansit and 26.0 grams of Siling Labuyo?

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Assessment

Directions: Answer the following questions below on a separate sheet of paper. 1. It is the reactant that produces a lesser amount of product. a. Excess Reactant c. Limiting Reactant b. Percent Yield d. Co-Factor

2. Which of the following describes relationship of of the number of moles and mass or reactant and products in a chemical reaction? a. Molality c. Balancing Equation b. Stoichiometry d. Percent Yield

3. It is the maximum amount of product you would expect from a reaction based on the amount of limiting reagent a. Theoretical yield c. Excess Reactant b. Limiting Reactant d. Product Difference

4. This refers to the reactants which were not used up after completion of the chemical reaction.. a. Excess Reagents b. Limiting Reagents b. Solute d. Solution

5. It is the process that involves rearrangement of the molecular or ionic structure of a substance to form a new substance or product. a. Chemical Equilibrium c. Chemical Symbols b. Chemical Reaction d. Stoichiometry

6. What is the expected value for percent yield? a. -1 b. 0-100 c. above 100 d. 95 to 100

7. Which of the following equation below is balanced?

a. Al+3O2→2Al2O3

b. 4Al+O2→2Al2O3

c. 4Al+3O2→Al2O3

d. 4Al+3O2→2Al2O3

8. In the equation Mg+HCl→MgCl2+H2, how many molecules of hydrogen do we need to make hydrogen balanced? a. 3 b. 6 c. 2 d. 7

9-12. Will 28.7 grams of SiO2 react completely with 22.6 grams of H2F2? If not, identify the limiting reagent. The balnced chemical equation for this reaction

is: SiO2+2H2F2→SiF4+2H2O

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Si=20.09 g/mole O= 16.00 g/mole H= 1.01 g/mole F= 19.00 g/mole

13-15. a. How many moles of chlorine gas can be produced if 4 moles of FeCl3

react with 4 moles of O2?

FeCl3 + O2Fe2O3 + Cl2 a. What is the limiting reactant? b. What is the excess reactant?

Additional Activities

Answer the following equation using your knowledge gain about limiting reactant.

1. The following quantities are placed in a container: 1.5 × 1024 atoms of hydrogen, 1.0 mol of sulfur, and 88.0 g of diatomic oxygen. H= 1.01 g/mol S= 32.10 g/mol O= 16.00 g/mol

a. What is the total mass in grams for the collection of all three elements? b. What is the total number of moles of atoms for the three elements? c. If the mixture of the three elements formed a compound with molecules that contain two hydrogen atoms, one sulfur atom, and four oxygen atoms, which substance is consumed first? d. How many atoms of each remaining element would remain unreacted in the change described in (c)?

2. What is the limiting reactant in a reaction that produces sodium chloride from 8 g of sodium and 8 g of diatomic chlorine?

3. Consider the following reaction:

2CuCl2 + 4KI  2 CuI + 4KCl + I2 Cu= 63.54 g/mol Cl= 35.45 g/mol I= 126.90 g/mol K= 39.10 g/mol

a. When 0.56 grams of CuCl2reacts with 0.64 grams of KI, how many

grams of I2 are formed? b. What is the limiting reactant?

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Answer Key

O c. FeCl b. 2 3

Cl of moles six a. 15. - 13 2

reagent. limiting the is it H2F2, of moles 0.568 only are there Because required.

C. Assuming that all of the silicon dioxide is used up, 0.478×21 or 0.956 moles of H2F2 are are H2F2 of moles 0.956 or 0.478×21 up, used is dioxide silicon the of all that Assuming C.

H2F2. the with react not do SiO2 of grams 28.7 0.568, to 0.478

use the ratio is is ratio the use Beca consumed. H2F2 of moles two every for SiO2 of mole one be must There

12 - 9

c 8. d 7. b 6. b 5.

a 4. a 3. b 2. c 1.

Answer

Assessment

a 15.

c 14.

d 13.

b 12.

c 11.

a 10.

b 9.

a 8.

c 7.

a 6.

grams. 7.48 get you 0.650,

by this Multiplying grams.

Pansit Hot 4 e. 11.5 is yield theoretical

2 d. the stoichiometry,

Pansit c. the to According 5.

Si b. SilingLabuyo b. mass. of vation conser of

N Si mol 8.81 = N 4 a. law the under reasonable is 4 3 2

N Si mol 7.15 Si= a. 2 100% under yield Any Yes. 4. 4 3

Jelly Guava 2 e. 2

3 d. 56% = 100% x (18.5/33) 3.

HBr 2. Jelly c.

H mol 2.48 HBr= Guava b. grams 33 2. 2

H mol 4.83 Al= 1. 5 a. 2Na3PO4 + Fe2(SO4)3 2

1 1 3Na2SO4 + FePO4 2 1. 1 

More What's Do Can I What Know I What

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References

Helmenstine, Anne Marie, Ph.D. "Percent Yield Definition and Formula." ThoughtCo. https://www.thoughtco.com/definition-of-percent-yield-605899 (accessed May 28, 2020).

Khan Academy. n.d. “Limiting Reagents and Percent Yield.” Khan Academy. Khan Academy. Accessed May 23, 2020. https://www.khanacademy.org/science/chemistry/chemical-reactions- stoichiome/limiting-reagent-stoichiometry/a/limiting-reagents-and-percent- yield. Kotz, J. C., P. M. Treichel, J. R. Townsend, and D. A. Treichel. "Stoichiometry: Quantitative Information about Chemical Reactions." In Chemistry and Chemical Reactivity, Instructor's Edition, 139-49. 9th ed. Stamford, CT: Cengage Learning, 2015 Lumen Learning. n.d. “Reaction Stoichiometry.” Lumen Learning Boundless Chemistry. PressBooks Lumen Learning. Accessed May 23, 2020. https://courses.lumenlearning.com/boundless-chemistry/chapter/reaction- stoichiometry/. Ruff MA, Bess. 2020. “How to Balance Chemical Equations.” WikiHOW, January. https://www.wikihow.com/Balance-Chemical-Equations. Staley, Dennis. Prentice Hall Chemistry. Boston: Pearson Prentice Hall, 2007.

UC Davis ChemWiki. "Stoichiometry and Balancing Reactions", CC-BY-NC-SA 3.0

Petrucci, Ralph H., William S. Harwood, Geoffery F. Herring, and Jeffry D. Madura. General Chemistry. 9th ed. New Jersey: Pearsin Prentice Hall, https://chem.libretexts.org/Bookshelves/Inorganic_Chemistry/Modules_an d_Websites_(Inorganic_Chemistry)/Chemical_Reactions/Limiting_Reagents2 007

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Physical

Science

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Physical Science How Energy is Produced and Managed First Edition 2020

Published by the Department of Education Secretary: Leonor Magtolis Briones Undersecretary: Diosdado M. San Antonio

Development Team of the Module

Writers: Amy B. Villar, Jennifer O. Tullao Editors: Robert G. Yumul Felipa A. Morada Reviewers: Ramonito O. Elumbaring, Angelica J. Macaraeg Felipa A. Morada Illustrator: Francis Victor A. Medrano Layout Artist: Mary Grace L. Asa, Pamela A. Lalusin Management Team: Wilfredo E. Cabral, Regional Director Job S. Zape Jr., CLMD Chief Elaine T. Balaogan, Regional ADM Coordinator Susan DL. Oribiana, Schools Division Superintendent Lorna R. Medrano, CID Chief Edita T. Olan, EPS-in-Charge, LRMS

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Physical Science How Energy is Produced and Managed

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Introductory Message

For the facilitator:

Welcome to the Physical Science 11 Alternative Delivery Mode (ADM) Module on How Energy is Produced and Managed!

In addition to the material in the main text, you will also see this box in the body of the module:

Notes to the Teacher This contains helpful tips or strategies that will help you in guiding the learners.

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For the learner:

Welcome to the Physical Science 11 Alternative Delivery Mode (ADM) Module on How Energy is Produced and Managed!

This module has the following parts and corresponding icons:

What I Need to Know This will give you an idea of the skills or

competencies you are expected to learn in the module.

What I Know This part includes an activity that aims to

check what you already know about the lesson to take. If you get all the answers correct (100%), you may decide to skip this module.

What’s In This is a brief drill or review to help you link

the current lesson with the previous one.

What’s New In this portion, the new lesson will be

introduced to you in various ways such as a story, a song, a poem, a problem opener, an activity or a situation.

What is It This section provides a brief discussion of the

lesson. This aims to help you discover and understand new concepts and skills.

What’s More This comprises activities for independent

practice to solidify your understanding and skills of the topic. You may check the answers to the exercises using the Answer Key at the end of the module.

What I Have Learned This includes questions or blank

sentence/paragraph to be filled in to process what you learned from the lesson.

What I Can Do This section provides an activity which will

help you transfer your new knowledge or skill into real life situations or concerns.

271

Assessment This is a task which aims to evaluate your

level of mastery in achieving the learning competency.

Additional Activities In this portion, another activity will be given

to you to enrich your knowledge or skill of the lesson learned. This also tends retention of learned concepts.

Answer Key This contains answers to all activities in the

module.

At the end of this module you will also find:

References This is a list of all sources used in developing this module.

The following are some reminders in using this module:

We hope that through this material, you will experience meaningful learning and gain deep understanding of the relevant competencies. You can do it!

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Week

What I Need to Know

This module was designed and written with you in mind. It is here to help you master how energy is harnessed from different sources: fossil fuels, biogas, geothermal, hydrothermal, batteries, solar cells, and biomass. The scope of this module permits it to be used in many different learning situations. The language used recognizes the diverse vocabulary level of students. The lessons are arranged to follow the standard sequence of the course. But the order in which you read them can be changed to correspond with the textbook you are now using.

This module contains discussion about the different sources of energy, how they are generated and managed.

After going through this module, you are expected to: 1. describe the different sources of energy; 2. give a brief summary of how energy is produced from different sources; 3. differentiate between renewable and non-renewable sources of energy; and 4. outline the pros and cons of the different sources of energy.

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What I Know

Choose the letter of the best answer. Write the chosen letter on a separate sheet of paper.

1. It can be converted in form, but not created nor destroyed. a. atom b. energy c. force d. matter

2. Energy that comes from sources that will run out or will not be replenished in our lifetimes—or even in many, many lifetimes a. kinetic b. non-renewable c. potential d. renewable

3. Organic matter from plants and animals (microorganisms) a. batteries b. biomass c. geothermal d. wind power

4. It includes hydrocarbons such as coal, oil, and natural gas that comes from organic remains of prehistoric organisms. a. batteries b. biogas c. fossil fuels d. solar power

5. The main source of energy in the Visayas region a. geothermal b. hydroelectric c. natural gas d. wind power

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6. This is “The People’s Power” because of the easy deployment of solar panels and where energy is shared among owners. a. biofuel b. geothermal c. hydroelectric d. solar energy

7. It is the world’s most abundant fossil fuel. a. coal b. natural gas c. oil d. petroleum

8. This is the kind of renewable energy that is used to create methane and alcohol which are fuels useful in energy production and in powering automobiles. a. biomass b. geothermal c. hydroelectric d. solar wind

9. He is the Italian physicist who invented the first battery. a. Alessandro Volta b. Antoine Lavoisier c. Dmitri Mendeleev d. Joseph Gay-Lussac

10. These are installed in strategic locations to harness the mechanical energy from wind. a. dams b. power plants c. wind turbines d. windmills

11. This renewable energy utilizes moving water to turn turbines. a. biomass b. geothermal c. hydroelectric d. solar wind

12. Around how many percent of electricity in Visayas is produced from geothermal power? a. 14% b. 38% c. 29% d. 45%

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13. This renewable source of energy is less of an environmental hazard compared to fossil fuels. a. batteries b. biomass c. fossil d. geothermal

14. These are installed in strategic locations where there is a substantial drop in elevation. a. dams b. power plants c. wind turbines d. windmills

15. The energy that comes from fossil fuels came from the sun through this process when the prehistoric plants were still alive. a. cytokinesis b. meiosis c. mitosis d. photosynthesis

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Lesson How is Energy Produced and 1 Managed

Energy is defined as the ability to do work. When work is done, energy is transferred from one object to another. Energy exists in different forms such as electrical and chemical energy. Most forms of energy can be classified as kinetic energy and potential energy. Kinetic energy is the energy possessed by moving matter. Things with kinetic energy can do work. Kinetic energy depends on the object’s mass and velocity. Potential energy is the energy stored in an object because of its position or shape.

What’s In

Activity 1.1 Word Pool

Direction: To get started, you have to choose the terms related to energy from the WORD POOL below. List down these words on the table on and write what you know about it on a separate sheet of paper.

potential nutrition stomach electricity geothermal atom rock solar typhoon renewable battery volcano biomass redshift respiration

Term What I know about it?

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Notes to the Teacher Ask learners to name different sources of energy and list them on the board. Add on the list sources that are not mentioned by the learners.

What’s New

Activity 1.2

The diagram shows the different sources of energy in the Philippines and the percentages of each source. Compare the main source of energy from the different regions of the Philippines.

Figure1. Gross Power Generation by Fuel (2013), Retrieved July 17, 2020, http:// www.eia.gov/todayinenergy/images/2015.03.06/chart2.png).

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Guide Questions: 1. What are the different sources of electricity in the Philippines? 2. Refer to the diagram above to complete the table below. Luzon Visayas Mindanao Main source of electricity Percentage Second Source of Electricity Percentage Third Source of Electricity Percentage

3. Based on the diagram, what can you say about the sources of energy from the different regions in the Philippines?

What is It

A power plant is an industrial facility that generates electricity from primary energy. Most power plants use one or more generators that convert mechanical energy into electrical energy in order to supply power to the electrical grid for society's electrical needs. The exception is solar power plants, which use photovoltaic cells (instead of a turbine) to generate this electricity. The type of primary fuel or primary energy flow that provides a power plant its primary energy varies. The most common fuels are coal, natural gas, and uranium (nuclear power). A substantially used primary energy flow for electricity generation is hydroelectricity (water). Other flows that are used to generate electricity include wind, solar, geothermal and tidal. Electrical sources can be broken down to two major groups: renewable and non-renewable sources. Renewable source is produced from sources that do not deplete or can be replenished within a human's life time. The most common examples include wind, solar, geothermal, biomass, and hydropower. This is in contrast to non-renewable source which is a natural resource that cannot be readily replaced by natural means at a quick enough pace to keep up with consumption.

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I. Renewable Sources 1. Geothermal

Geothermal power utilizes the heat energy from the earth’s crust. This heat energy heats up rocks which, in turn, heats up nearby groundwater. The Malitbog Geothermal Power Station is a 232.5 MW geothermal power plant or an earth steam turbined electric generator--the world's largest geothermal power plant under one roof located in Malitbog, Kananga, Leyte, Philippines. The power plant is one of four operating in the Leyte Geothermal Production Field. Geothermal energy is produced by the heat of Earth's molten interior. This energy is harnessed to generate electricity when water is injected deep underground and returns as steam (or hot water, which is later converted to steam) to drive a turbine on an electric power generator that produces electricity. Geothermal energy is less of an environmental hazard compared to fossil fuels though it still has some emissions of carbon dioxide, nitrous oxide, and sulfur dioxide.

Some of the operational geothermal power plants in the Philippines are:

 Malibarara Geothermal Power Plant in Sto. Tomas, Batangas

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 Makban Geothermal Power Plant and Makban Binary Geothermal Power Plant in Bay, Laguna  Tiwi Geothermal Power Plant in Tiwi, Albay  Bacon Manito Geothermal Power Plant in Sorosogon  Unified Leyte Geothermal Power Plant Tongonan Geothermal Power Plant in Leyte  Southern Negros Geothermal Production Field – Nasulo Geothermal Power Plant and Palinpinon Geothermal Power Plant in Valencia Negros Occidental

2. Hydroelectric

Hydroelectric power (hydropower) is derived from the energy of falling or moving water to generate electricity. Among other purposes, water is widely used to produce electricity. Hydropower is a proven, mature, predictable, and price competitive technology. A number of on- and off-grid hydropower plants have been built throughout the country, including impounding dams and run-of-river types. Impounding dams are able to supply energy during peak and off-peak hours while run-of-river types supply electricity whenever capable, depending on the volume of water that is discharged from the watersheds. A turbine converts the kinetic energy of falling water into mechanical energy. Then a generator converts the mechanical energy from the turbine into electrical energy. The generator power is stepped up to a higher voltage from the substation, and then exported for transmission.

Some of the operational hydroelectric power plants in the Philippines are:

 Palakpakin Hydroelectric Power Plant in San Pablo, Laguna  Balugbog Hydroelectric Power Plant in Narcarlan, Laguna  Cantingas Hydroelectric Power Plant in San Fernando, Romblon

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3. Wind power

While an electric fan uses electricity to produce wind, a wind turbine uses wind to produce electricity. A wind turbine can generate megawatts of power, depending on the weather conditions. In fact, an indicator for a potential wind farm site is the presence of flagging trees or trees that are bent like how a flag would look like due to strong winds. Because of the vast land area a wind farm occupies, unused areas can be co-located with agricultural crops or even a solar farm. Wind has been used in centuries to move ships and pump water. Wind turbines are installed in strategic locations to harness the mechanical energy from wind. Some of the most recent developments are the Bangui Wind Farm, Burgos Wind Farm, and Caparispisan Wind Farm in Ilocos Norte, the Wind Energy Power System in Oriental Mindoro, San Lorenzo Wind Farm in Guimaras, Nabas Wind Farm in Aklan and Pililla Wind Farm in Rizal.

4. Solar Cells

If plants photosynthesize using sunlight, electric-powered technologies can also use sunlight for energy. Solar power is a variable energy source that is dependent on the cycle of the sun. The Philippines, being situated near the equator, has many potential sites where solar energy may be harnessed. With recent technology, solar power systems can be both applied to on- and off-grid areas. Aggressive economic growth for the country is not far behind. As long as there is sunlight, solar power will always be available. Solar power technology may not generate energy at night but it is capable of supplying electricity to the grid at daytime. A solar cell, or photovoltaic cell, is an electrical device that converts the energy of light directly into electricity by the photovoltaic effect, which is

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a physical and chemical phenomenon. It is a form of photoelectric cell, defined as a device whose electrical characteristics, such as current, voltage, or resistance, vary when exposed to light. Individual solar cell devices are often the electrical building blocks of photovoltaic modules, known colloquially as solar panels.

Some of the operational solar power plants in the Philippines are:

 Lian Sola Power Project and Calatagan Solar Power Project in Calatagan, Batangas  Cavite Economic Zone Solar Power Project in Rosario and General Trias, Cavite  CW Home Depot Solar Power Project and Central Mall Binan Solar Power Plant in Biñan City, Laguna

Solar energy is also known as “The People’s Power,” referring to the easy deployment of solar panels and the introduction of “community solar gardens” where energy is shared among owners.  Solar energy is abundant, requires low maintenance, and is environmentally- friendly.  Emissions associated with the manufacture of solar panels are present but very minimal compared to pollution caused by burning fossil fuels.  Two of the harmful emissions from the manufacture of solar panels are nitrogen trifluoride and sulfur hexafluoride.  Both are potent greenhouse gases.  Some disadvantages of solar energy are: it is expensive, requires rare metals, and requires a good amount of space. Thankfully, the technology is continuously improving.

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 5. Biomass

Biomass refers to organic matter from plants and animals (microorganisms). Organic wastes such as crop remains, manure, and garbage usually left to rot, can be used for electricity generation. Rice husks and/or bagasse are burned as fuel to boil water. The steam from the boiling water is used to run steam turbines, which in turn drive generators to produce electricity.

 Wood is also a biomass fuel.  As long as we replenish the trees that we cut, biomass can be a sustainable energy source.  Biomass is used to create methane and alcohol which are fuels useful in energy production and in powering automobiles.  Production of biogas or biofuels involves the action of microorganisms that break down organic matter in a multi-step process.  Technologies utilizing biomass are continuously evolving in order to improve efficiency.

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II. Non-renewable Sources

1. Fossil fuels

Coal, oil and gas are fossil fuels, which have been formed over the last 600 million years. Coal is the fossilized remains of huge forests which covered many parts of the world in prehistoric times and hence contains biomass. As the trees and plants died, they were covered in layers of silt and sand and, under great pressure, gradually became formed into coal deposits.

 Coal is the world’s most abundant fossil fuel. It is relatively inexpensive and is readily available.  The formation of fossil fuels is due to a series of geologic processes where the remains of organic life are accumulated in the ocean bottom and are buried to eventually become part of the geosphere.  They are buried to depths having high temperature and pressure where they are converted to oil, natural gas, or coal.  In the Philippines, around 69% of our electricity is derived from fossil fuels (coal, oil, natural gas, biomass).  In the world, around 75% of our energy is generated by combustion of fossil fuels.

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 Power plants burn fossil fuels and the heat generated during this process is used to turn water into steam and this turns the turbines.

2. Electrochemical (batteries)

A battery is a device that stores chemical energy and converts it to electrical energy. The chemical reactions in a battery involve the flow of electrons from one material (electrode) to another, through an external circuit. The flow of electrons provides an electric current that can be used to do work. There are three main components of a battery: two terminals made of different chemicals (typically metals), the anode and the cathode; and the electrolyte, which separates these terminals. The electrolyte is a chemical medium that allows the flow of electrical charge between the cathode and anode.

Batteries, compared to other sources, have low intensity but they are commonly used since they are portable and efficient.

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What’s More

Activity 1.3 Table Summary

Summarize your understanding about the different sources of energy by filling out the table below. Use a separate sheet of paper for your answer.

Description Sources Examples Advantages/Disadvantages

Fossil Fuel

Electrochemical Cells

Geothermal

Hydroelectric

Wind

Solar Cells

Biomass

What I Have Learned

Activity 1.4 Construct a Venn Diagram

Point out the similarities and differences between renewable and non-renewable sources of energy by using a Venn diagram on a separate sheet of paper.

Non-Renewable Renewable Sources Sources

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What I Can Do

Activity 1.5 Create an Acrostic Poem

Direction: Now that you have the knowledge about the different sources of energy, create an acrostic poem using the word ENERGY. Rubrics

Criteria Excellent Merit Achieved Needs Score (4pts) (3pts) (2pts) Improvement (1pt)

Content Information are Information are Information is Information is clearly presented clearly clear unclear and written and ordered in presented and in random order such a way that it ordered Order of brings a full information picture of the does not clearly material show Creativity It is visually Visually inviting Visually Readable inviting and easy and easy to read pleasing and to read readable Spelling and All spelling and Some spelling Some spelling Notable spelling and Grammar grammar are and grammar and grammar grammar error correct error error Punctuality Submitted on Submitted on Submitted on Submitted after the time time time deadline TOTAL Highest possible score: (4x4)/4= 4 components

Sample Score Sheet

Adjectival Rating Rating Grade Range Range Excellent 3.4-4.0 95-100 Merit 2.6-3.3 88-94 Achieved 1.8-2.5 81.87 Needs 1-1.7 75-80 Improvement

Criteria Score Content 3 Creativity 3 Spelling and Grammar 3 Punctuality 4 TOTAL 13 13pts/4categories= 3.25

Learner is within the Merit range and the teacher may choose a grade within this range.

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Assessment

Modified True or False. Read each statement carefully. Write True if the statement is correct; if the statement is FALSE, change the italicized word to make it true. Write your answer on a separate sheet of paper. ______1. Biomass is used to create methane and alcohol which are fuels useful in energy production and in powering automobiles. ______2. Electrical sources can be broken down into three major groups. ______3. Hydroelectric power utilizes the heat energy from the earth’s crust.

______4. Solar energy is abundant, requires low maintenance, and is environmentally-friendly.

______5. Wind turbines are installed in strategic locations to harness the mechanical energy from wind.

______6. The cushion is a chemical medium that allows the flow of electrical charge between the cathode and anode.

______7. The world’s most abundant fossil fuel is natural gas. ______8. The most common fuels are coal, natural gas, and uranium (nuclear power).

______9. A generator converts the kinetic energy of falling water into mechanical energy.

______10. Batteries have high intensity but they are commonly used since they are portable and efficient. ______11. Geothermal energy is less of an environmental hazard compared to fossil fuels. ______12. Wastes such as crop remains, manure, and garbage are good sources of biomass. ______13. Nonrenewable source is produced from sources that do not deplete or can be replenished within a human's life time. ______14. An electric fan uses electricity to produce wind. ______15. Water is widely used to produce electricity.

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Additional Activities

Activity 1.6 Direction: Make either a poster, a flyer, or a brochure on a product (such as fuels, household, or personal care products) indicating its uses, properties, mode of action, and precautions.

Answer Key

vary. may Answers 3.

17% 7% 10%

Percentage

Electricity

Coal Oil Hydroelectric of Source Third

22% 42% 34% Percentage

Electricity

Oil Coal gas Natural of Source Second

52% 49% 47% Percentage

electricity

Hydroelectric Geothermal Coal of source Main

Mindanao Visayas Luzon

thers. o and

1. The different sources of energy in the Philippines are coal, natural gas, oil, geothermal, hydroelectric hydroelectric geothermal, oil, gas, natural coal, are Philippines the in energy of sources different The 1.

New What’s

manure renewable Biomass

Farm Wind Bangui renewable Wind

Plant Power ectric Hydroel IV Pulangi renewable Hydroelectric

Malitbog Geothermal Power Station Power Geothermal Malitbog renewable Geothermal

batteries renewable - non Electrochemical

coal renewable - non Fuel Fossil

Source

Example Electrical of Type

More What’s

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Mindanao 15.

True 14.

Volta Alessandro 13.

True 12.

low 11.

True 10.

True 9.

coal 8.

True 7.

Geothermal 6.

True 5.

True 4.

renewable - non 3.

two 2.

. vary may s Answer True 1.

Activities Additional Assessment

. vary may s Answer . vary may s nswer A . vary may s Answer

Do Can I What Learned Have I What More What's

D 15.

A 14.

D 13.

B 12.

C 11.

C 10.

A 9.

A 8.

biomass 7. A 7.

battery 6. D 6.

renewable 5. A 5.

solar 4. C 4.

geothermal 3. B 3.

electricity 2. B 2.

potential 1. B 1.

In What’s Know I What

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References

Website:

Empowered. “Renewable Energy Decade Report 2008-2018.”Accessed July 22, 2020,https://www.doe.gov.ph/sites/default/files/pdf/issuances/20081216- ra-09513-gma.pdf

“Energy Education.” Accessed July 17, 2020, https://energyeducation.ca/ encyclopedia/Power_plant

Wikipedia. “Malitbog Geothermal Power Station”, Accessed July 20, 2020 https://en.wikipedia.org/wiki/Malitbog_Geothermal_Power_Station

“Gross Power Generation by Fuel (2013).” Accessed July 18, 2020, http:// www.eia.gov/todayinenergy/images/2015.03.06/chart2.png).

“Our Energy Sources, Geothermal – The National Academies”, Accessed July 19, 2020 http://needtoknow.nas.edu/energy/energy-sources/renewable- sources/geothermal/#:~:text=Geothermal%20energy%20is%20produced%20 by,on%20an%20electric%20power%20generator.

Energy Matters. “How is Hydroelectricity Generated”, Accessed July 21, 2020 https://www.enbridge.com/energy-matters/energy-school/hydro- generation#:~:text=Hydroelectric%20power%20is%20a%20renewable,moving %20water%20to%20produce%20electricity.&text=As%20the%20water%20flo ws%20down,turbine's%20mechanical%20energy%20into%20electricity.

Wikipedia. ”Wind Power in the Philippines”, Accessed July 22, 2020 https://en.wikipedia.org/wiki/Wind_power_in_the_Philippines

Wikipedia. “Solar Cell”, Accessed July 20, 2020 https://en.wikipedia.org/ wiki/Solar_cell

Mary Bates. School of Engineering: “How Does A Battery Work?”, Accessed July 17, 2020 https://engineering.mit.edu/engage/ask-an-engineer/how-does-a- battery-work/

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For inquiries or feedback, please write or call:

Department of Education - Bureau of Learning Resources (DepEd-BLR)

Ground Floor, Bonifacio Bldg., DepEd Complex Meralco Avenue, Pasig City, Philippines 1600

Telefax: (632) 8634-1072; 8634-1054; 8631-4985

Email Address: [email protected] * [email protected]

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Physical

Science

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Physical Science Active Ingredient(s) of Cleaning Products Used at Home First Edition 2020

Published by the Department of Education Secretary: Leonor Magtolis Briones Undersecretary: Diosdado M. San Antonio

Development Team of the Module

Writers: Jennifer O. Tullao, Amy B. Villar Editors: Robert G. Yumul Felipa A. Morada Reviewers: Ramonito O. Elumbaring, Angelica J. Macaraeg Felipa A. Morada Illustrator: Francis Victor A. Medrano Layout Artist: Mary Grace L. Asa Pamela A. Lalusin Management Team: Wilfredo E. Cabral, Regional Director Job S. Zape Jr., CLMD Chief Elaine T. Balaogan, Regional ADM Coordinator Susan DL. Oribiana, Schools Division Superintendent Lorna R. Medrano, CID Chief Edita T. Olan, EPS-in-Charge, LRMS

Department of Education – Region IV-A CALABARZON

Office Address: Gate 2 Karangalan Village, Barangay San Isidro Cainta, Rizal 1800 Telefax: 02-8682-5773/8684-4914/8647-7487 E-mail Address: [email protected]

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Physical Science Active Ingredient(s) of Cleaning Products Used at Home

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Introductory Message

For the facilitator:

Welcome to the Physical Science 11 Alternative Delivery Mode (ADM) Module on Active Ingredient(s) of Cleaning Products Used at Home!

In addition to the material in the main text, you will also see this box in the body of the module:

Notes to the Teacher This contains helpful tips or strategies that will help you in guiding the learners.

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For the learner:

Welcome to the Physical Science 11 Alternative Delivery Mode (ADM) Module on Active Ingredient(s) of Cleaning Products Used at Home!

This module has the following parts and corresponding icons:

What I Need to Know This will give you an idea of the skills or

competencies you are expected to learn in the module.

What I Know This part includes an activity that aims to

check what you already know about the lesson to take. If you get all the answers correct (100%), you may decide to skip this module.

What’s In This is a brief drill or review to help you link

the current lesson with the previous one.

What’s New In this portion, the new lesson will be

introduced to you in various ways such as a story, a song, a poem, a problem opener, an activity or a situation.

What is It This section provides a brief discussion of the

lesson. This aims to help you discover and understand new concepts and skills.

What’s More This comprises activities for independent

practice to solidify your understanding and skills of the topic. You may check the answers to the exercises using the Answer Key at the end of the module.

What I Have Learned This includes questions or blank

sentence/paragraph to be filled into process what you learned from the lesson.

What I Can Do This section provides an activity which will

help you transfer your new knowledge or skill into real life situations or concerns.

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Assessment This is a task which aims to evaluate your

level of mastery in achieving the learning competency.

Additional Activities In this portion, another activity will be given

to you to enrich your knowledge or skill of the lesson learned. This also tends retention of learned concepts.

Answer Key This contains answers to all activities in the

module.

At the end of this module you will also find:

References This is a list of all sources used in developing this module.

The following are some reminders in using this module:

We hope that through this material, you will experience meaningful learning and gain deep understanding of the relevant competencies. You can do it!

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Week

What I Need to Know

This module was designed and written with you in mind. It is here to help you master the active ingredients of cleaning products used at home. The scope of this module permits it to be used in many different learning situations. The language used recognizes the diverse vocabulary level of students. The lessons are arranged to follow the standard sequence of the course. But the order in which you read them can be changed to correspond with the textbook you are now using.

Knowledge of chemicals used on the different household cleaning products is very important. On this module, it focuses on the identification of the active ingredient(s) of cleaning products used at home.

After going through this module, you are expected to identify the active ingredient(s) of cleaning products at home.

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What I Know

Choose the letter of the best answer. Write the chosen letter on a separate sheet of paper.

1. The type of cleaning products which many of the ingredients can be manufactured from plants. a. astringent b. bleaches c. detergent products d. dishwashing liquid

2. An active component of bleach can remove stains. a. chlorine b. magnesium c. potassium d. sulfur

3. This cleaning product provides the chemical energy to help clean and remove food soil from different types of cooking and serving items. a. astringent b. bleaches c. detergent products d. dishwashing liquid

4. This helps to disinfect and sanitize the materials and furniture in our home. a. astringent b. bleaches c. detergent products d. dishwashing liquid

5. This can prevent the spread of infectious diseases and control allergens, such as dust and mold. a. cleaning product b. cooking utensils c. electrical appliances d. vehicles

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6. These are liquid cleansers for cleaning dishes, plastics, and many other surfaces. a. astringent b. bleaches c. detergent products d. dishwashing liquid

7. Sodium hydroxide and ______are the most commonly used alkali in soap and detergents. a. calcium hydroxide b. cesium hydroxide c. magnesium hydroxide d. potassium hydroxide

8. This is known as washing soap or washing-up liquid that is used for hand washing of glasses, plate, cutlery, and cooking utensils in a sink or bowl. a. dishwashing gel b. dishwashing liquid c. dishwashing powder d. dishwashing tablet

9. Mixing chlorine bleach with ammonia or vinegar can release what kind of poisonous gas? a. carbon monoxide b. chlorine c. nitrous oxide d. sulfur

10. This is a reducing bleach that works by changing the double bonds of a chromosphere into single bonds. a. increasing bleach b. non-oxidizing bleach c. oxidizing bleach d. reducing bleach

11. Cleaning your home is very important. It includes scrubbing, removing of dust, grease, and ______. a. clothes b. furniture c. food waste d. shoes

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12. Which of the following is the best practice to have clean and healthy living? a. Eat at the right time b. Exercise daily c. Do handwashing d. Wear safety gadgets

13. Which of the following must be properly cleaned? a. bathroom b. kitchen top c. utensils d. all of the above

14. What will you use to perform a good handwashing? a. detergent b. dishwashing liquid c. soap d. wax

15. In order to prevent any harm in using the cleaning products at home, one must: a. Buy one product only. b. Read carefully the product information. c. Patronize the most popular name of a product. d. Check the cheapest product available in the market.

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Lesson Active Ingredient(s) of Cleaning Materials Used at 1 Home

Home is our haven especially when we are so tired in our whole day work in school or office. In this time of pandemic, the cleanliness of our home is very important. Good housekeeping requires high standard of cleanliness or the absence of dirt and its sanitation as well, or the absence of disease-causing organisms like bacteria. All housekeeping tasks need the use of the right tool for the right job. No single product can provide optimum performance on all surfaces and all soils. It is not surprising that many different household cleaners are available in the market. They are formulated to clean efficiently and conveniently in many different situations found at home.

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What’s In

Activity 1.1 Chemical reaction occurs when there is enough energy between reactants and creates products. The reaction can increase or decrease temperature which is one of the reasons that cleaning household products can burn skin or cause irritation. 1. What are the things you already know about the following concepts? 2. In what way will the following concepts be useful in understanding how chemical household cleaning products works effectively. Give a possible explanation. a. Energy b. Chemical reactions Let us see how these concepts occur in our lesson. Note: Be careful on handling household cleaning products.

Notes to the Teacher Let the learner look for the cleaning products available in their home that will be used in the activity. Instruct the learner to be very careful in handling the household cleaning products.

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What’s New

Activity 1.2 Fruity Agents Direction: Aside from being our food, give the other use of these fruits/vegetables. Explain why these fruits/vegetables could be useful as cleaning materials or agents. “Fruits/ Vegetables as Cleaning Agents” Fruits/vegetables Use

1. calamansi

2.lemons

3. papaya

4. tomatoes

5. potatoes

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What is It

Active Ingredients of Cleaning Products Used at Home

There are lots of cleaning products we use daily in our home, office, or school. These cleaning products play an important vital role in order to make our home spick and span. They also help in safely and effectively removing dirt, germs and other contaminants. They can also prevent the spread of infectious diseases and control allergens, such as dust and mold, in order to keep us healthy. Cleaning products also enable us to care for our homes and possessions.

There are different kinds of cleaning products. These are laundry detergents, bleaches, dishwashing products and other household cleaners. Active ingredients are found in different household cleaning products. They may give different side effects to human. They can give either positive or negative side effects to us. So before using these cleaning materials be sure to read first the instructions. Don’t forget to follow all precautionary and safety measures before using them. Here are some of the active ingredients found in different cleaning materials we use at home.

1. Alcohol Ethoxylate (AE) Alcohol ethoxylates are a class of compounds that are commonly used throughout many industrial practices and commercial markets. These compounds are synthesized via the reaction of a fatty alcohol and ethylene oxide, resulting in a molecule that consists of two main components, (1) the oleophilic, carbon-rich, fatty alcohol and (2) the hydrophilic, polyoxymethylene chain.

Alcohol ethoxylate surfactants enhance the mixing and solubilization of oil and water by having these contrasting sections within the same compound. With this unique structure, a single molecule can inhabit the interface of two immiscible phases (i.e. oil and water), effectively bringing them closer together and lowering the interfacial energy associated between them.

Because these compounds are surfactants, they can be used whenever oily substances encounter water or a surface. It can be

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used as detergents, wetting agents, emulsifiers, degreasers and emollients in many lines of commercially available products and industrial practices.

2. Sodium Alkyl Sulfates Sodium alkyl sulfate are members of alkyl sulfates. They are water-soluble and can form soap bubbles. The chemical formula is CnH2n+1OSO2ONa.

It can be used in detergents, dish washing liquids, shower gels, shampoos, hair conditioners and fabric softeners. It can also be used as fire extinguishing agent, because it is not flammable. In the cosmetic industry it is used as an emulsifier to mix oily and water-soluble compounds for toothpaste or moisturizing products. It can produce irritating vapors when heated, consisting of carbon dioxide, carbon monoxide, sulfur dioxide and others. As all detergents it can irritate skin and eyes. If swallowed, it will cause nausea or vomiting.

3. Amine Oxide An amine oxide, also known as amine-N-oxide and N-oxide, is a chemical compound that contains the functional group R3N+–O−, an N–O bond with three additional hydrogen and/or hydrocarbon side chains attached to Long-chain alkyl amine oxides are used as nonionic surfactants and foam stabilizers.

Amine oxides are highly polar molecules and have a polarity close to that of quaternary ammonium salts. Small amine oxides are very hydrophilic and have an excellent water solubility and a very poor solubility in most organic solvents.

4. Ammonia Ammonia is a colorless, soluble alkali gas that occurs naturally in the environment. It is a chemical containing one nitrogen and three hydrogen atoms bonded together. It was traditionally used in many household cleaners, though today it's still found in glass cleaner, all-purpose cleaners, and smelling salts. When used in cleaning compounds, it’s called “household ammonia.”

Ammonia fumes are powerful irritant, potentially harming your skin, eyes, nose, lungs and throat. When found in oven cleaners and window cleaning formulations, it is an irritant to the mucous membranes. When working with ammonia, wearing heavy-duty gloves, goggles, and a face mask are smart precautions to protect your health.

5. Sodium hypochlorite Sodium hypochlorite also known as bleach is another alkali disinfectant. Bleach works by oxidizing or breaking down the molecular bonds of stains and germs.

Another useful but dangerous cleaner it also has strong corrosive properties that may do serious damage to the human body. Ammonia and bleach are a

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particularly dangerous combination, creating potentially deadly gases when mixed. Never store these two chemicals in the same place.

Bleach in the bottle is generally a five percent solution. Toxic chlorine gas can be formed if bleach is mixed with acids, such as bowl cleaners.

6. Ethanol Ethanol is a natural byproduct of plant fermentation and can be produced through the hydration of ethylene. It mixes easily with water and many organic compounds, and makes an effective solvent for use in paints, lacquers and varnish, as well as personal care and household cleaning products.

Ethanol is highly flammable and should not be used near open flames. Ethanol inhalation can cause coughing or headaches. 7. Phenol Phenol, any of a family of organic compounds characterized by a hydroxyl (―OH) group attached to a carbon atom that is part of an aromatic ring. Besides serving as the generic name for the entire family, the term phenol is also the specific name for its simplest member, monohydroxybenzene (C6H5OH), also known as benzenol, or carbolic acid.

Phenols are similar to alcohols but form stronger hydrogen bonds. They are more soluble in water than are alcohols and have higher boiling points. Phenols occur either as colorless liquids or white solids at room temperature and may be highly toxic and caustic.

Phenols are widely used in household products and as intermediates for industrial synthesis. For example, phenol itself is used (in low concentrations) as a disinfectant in household cleaners and in mouthwash. Phenol may have been the first surgical antiseptic. In 1865 the British surgeon Joseph Lister used phenol as an antiseptic to sterilize his operating field.

8. Quaternary ammonium The quaternary ammonium compounds (or quats) are a family of low-level disinfectants (according to Spaulding) with most quats being derived from benzalkonium. Quats are reacted to provide a variety of chain lengths and molecular structures so that the mix of quats used in the disinfectant provide a wider range of efficacy than a single chain.

Quats are generally used to disinfect countertops, toilets and other high touch environmental surfaces and floors. Quaternary ammonium compounds are cationic disinfectants. This means the quats chain carries a positive (plus) charge on one end of the molecule; many soils and soaps/detergents carry an anionic or negative (minus) charge.

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Quats can also bind with, or be absorbed by, materials and fibers including cotton (e.g., cleaning rags and mops). Quats generally take 3-10 minutes to disinfect and should be used with cleaning tools that are tested to be compatible.

9. Sodium percarbonate. Sodium percarbonate is a powder that releases hydrogen peroxide, and very concentrated. It is a granulated powder which can be nice for scrubbing stains and stuck-on-gunk off dishes. Scouring powder is made from hydrogen peroxide. It can be made into a paste, too, and used on tile grout and tough stains.

In using this product, follow and read the instructions carefully. Be very careful in handling all household cleaning products.

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What’s More

Activity 1.3 Product Exploration

Direction: With your cleaning products available at hand, read the product information on the packaging. Fill out what is ask on the table below using the product information. During the activity, observe the products with caution, particularly in smelling and touching as they may have harmful effects upon contact. Write your answer on a separate sheet.

nes Product

Product Description Active/Major Ingredient Guideli in the using product Precautions in the using product

Bleach (DO NOT TOUCH with BARE HANDS)

Detergent soap

Dishwashing liquid

Toilet bowl cleaner (DO NOT TEACH with BARE HANDS) After filling up the table, check the common active ingredients present in all cleaning products.

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What I Have Learned

Activity 1.4 Product Discovery Direction: 1.With the following ingredients, specify their use as household cleaning materials. a. garlic b. onion c. salt d. vinegar 2. What properties they possessed to be considered as cleaning products.

“Ingredients as Household Cleaning Products” Ingredients Uses Properties garlic onion salt vinegar

3. Explain why these are useful not only as ingredients but also as household cleaning products. 4. Take all the necessary care in doing the activity. 5. Wear necessary gears in performing the activity. 6. Write your output in a separate sheet of paper.

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What I Can Do

Activity 1.5 Direction: 1.What are the alternative natural materials can be used in cleaning the following: a. food stain on clothes b. kitchen sink c. bad smell/odor inside refrigerator

2. Give your opinion why these alternative materials can be used as household cleaning material.

3. Write your answer on a separate sheet of paper.

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Assessment

Direction: Write T if statement is true and F if the statement is false and choose the word or set of words that make it incorrect. Write your answers on a separate sheet of paper.

1.Sodium percarbonate is a granulated powder that can be used in scrubbing stains.

2. Alcohol Ethoxylate are being synthesized through the reaction of a fatty alcohol and ethylene oxide.

3. Quaternary ammonium are compounds that belong to the family of high-level disinfectants.

4. Sodium alkyl sulfate are water-soluble sulfates that can form soap bubbles.

5. Phenols form stronger hydrogen bonds and more soluble in water than alcohols.

6. Small amine oxides are very hydrophilic and have an excellent water solubility.

7. Bleach is the other name for sodium hypochlorite.

8. Alcohol ethoxylate is an alkyl sulfate that enhances the mixing and solubilization of oil and water.

9. Quat is a powder that releases hydrogen peroxide which can be used for scrubbing stains.

10. Ethanol is a byproduct of plant fermentation and produced through the hydration of ethylene.

11. All cleaning agents can irritate skin and eyes and can cause nausea or vomiting if swallowed.

12. Ethanol is non-flammable, but inhalation can cause coughing or headaches.

13. Ammonia is a soluble alkali gas which contains one nitrogen and three hydrogen atoms bonded together.

14. Ethoxylate surfactants enhance the mixing and solubilization of oil and water.

15. Ammonia fumes are powerful irritants that can cause harm to your skin, eyes, nose, lungs and throat.

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Additional Activities

Activity 1.6 Direction: Compose a jingle related to the topic active ingredients of cleaning agents. Write your output in a separate sheet of paper. Rubrics

Criteria Excellent Merit Achieved Needs Score (4pts) (3pts) (2pts) Improvement (1pt) Content Information Information Information Information is are clearly are clearly is clear unclear and presented and presented written in Order of ordered in and ordered random order information such a way does not that it brings clearly show a full picture of the material Creativity It is visually Visually Visually Readable inviting and inviting and pleasing and easy to read easy to read readable Spelling and All spelling Some Some Notable spelling Grammar and grammar spelling and spelling and and grammar are correct grammar grammar error error error Punctuality Submitted on Submitted Submitted Submitted after time on time on time the deadline TOTAL Highest possible score: (4x4)/4= 4 components

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Answer Key

acid acetic -

Vinegar

nature in ionic - Salt

acid

Sulphasillic Sulphasillic - Onion

allicin -

Garlic

Properties:

grease

removes dirt and and dirt removes

disinfectant,

- inegar V

agent scouring - Salt

rust removes - Onion

tops cleaning products

disinfectant, disinfectant, - Garlic

learner. the of

cleaning available

Use: depending on the insight insight the on depending the on depending

Answers may vary vary may Answers vary may Answers

Learned

Do Can I What have I What

More What’s

D 15.

14.

vary. may Answers D 13.

rust removes - Potato C 12.

metal C 11.

clean clean - Tomatoes D 10.

remover B

9. stain stain - Papaya B 8.

odor removes D

7. natural bleach; bleach; natural D 6.

antiseptic; - Lemon A 5.

vegetables. odor C 4.

available fruits and and fruits available and stain removes D 3.

depending on the the on depending bleach, - Calamansi A 2.

Answers may vary vary may Answers Use: C 1.

New at’s Wh In What's Know I What

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Answer Key

T 15.

T 14.

T 13.

flammable

- non - F 12.

T 11.

T 10.

Quat - F 9.

sulfate

alkyl alkyl - F 8.

T 7.

products T 6.

available cleaning cleaning available T 5.

depending on the the on depending T 4.

Answer may vary vary may Answer low - F 3.

T 2.

T 1. Activities

Additional Additional Assessment

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References

Website:

“Amine oxide”, Accessed July 17, 2020, https://www.clinisciences.com/ en/buy/cat-amine-oxides-1830.html

“Chem 101: What you need to know about active ingredients?”, Accessed May 20, 2020, cleanlink.com. https://www.cleanlink.com/hs/article/Chem-101- What-you-need-to-know-about-active-ingredients--372

“Chemicals Found in Household Products Chapter 6, Lesson 1”, Accessed May 20, 2020, study.com. https://study.com/academy/lesson/chemicals-found-in- household-products.html

‘Ethanol”, Accessed July 17, 2020, https://www.chemicalsafetyfacts.org/ethanol/

“Phenol”, Accessed July 17, 2020, https://www.britannica.com/science/phenol

“Sodium alkyl sulfate”, Accessed July 17, 22020, https://en.wikipedia.org/wiki/ Sodium_alkyl_sulfate

“What is Alcohol Ethoxylate?”, Accessed July 17,2020,https://www.oxiteno.us/ what-is-alcohol-ethoxylate-uses/#:~:text=Alcohol%20ethoxylates%20are% 20 a%20class,industrial%20practices%20and%20commercial%20markets.&text =Alcohol%20ethoxylate%20surfactants%20enhance%20the,sections%20with in%20the%20same%20compound.

Commission on Higher Education. Teaching Guide for Senior High School: Physical Science. Book. https://drive.google.com/file/d/0B869YF0KEHr7SHFG VG5mVFFhcXc/view. Creative Commons Attribution-NonCommercial- ShareAlike 4.0

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For inquiries or feedback, please write or call:

Department of Education - Bureau of Learning Resources (DepEd-BLR)

Ground Floor, Bonifacio Bldg., DepEd Complex Meralco Avenue, Pasig City, Philippines 1600

Telefax: (632) 8634-1072; 8634-1054; 8631-4985

Email Address: [email protected] * [email protected]

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Physical Science

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Physical Science Use of the Other Ingredients in Cleaning Agents First Edition 2020

Published by the Department of Education Secretary: Leonor Magtolis Briones Undersecretary: Diosdado M. San Antonio

Development Team of the Module

Department of Education – Region IV-A CALABARZON

Office Address: Gate 2 Karangalan Village, Barangay San Isidro Cainta, Rizal 1800 Telefax: 02-8682-5773/8684-4914/8647-7487 E-mail Address: [email protected]

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Physical Science Use of the Other Ingredients

in Cleaning Agents

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Introductory Message

For the facilitator:

Welcome to the Physical Science 11 Alternative Delivery Mode (ADM) Module on Use of the Other Ingredients in Cleaning Agents!

In addition to the material in the main text, you will also see this box in the body of the module:

Notes to the Teacher This contains helpful tips or strategies that will help you in guiding the learners.

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For the learner:

Welcome to the Physical Science 11 Alternative Delivery Mode (ADM) Module on Use of the Other Ingredients in Cleaning Agents!

This module has the following parts and corresponding icons:

What I Need to Know This will give you an idea of the skills or

competencies you are expected to learn in the module.

What I Know This part includes an activity that aims to

check what you already know about the lesson to take. If you get all the answers correct (100%), you may decide to skip this module.

What’s In This is a brief drill or review to help you link

the current lesson with the previous one.

What’s New In this portion, the new lesson will be

introduced to you in various ways such as a story, a song, a poem, a problem opener, an activity or a situation.

What is It This section provides a brief discussion of the

lesson. This aims to help you discover and understand new concepts and skills.

What’s More This comprises activities for independent

practice to solidify your understanding and skills of the topic. You may check the answers to the exercises using the Answer Key at the end of the module.

What I Have Learned This includes questions or blank

sentence/paragraph to be filled into process what you learned from the lesson.

What I Can Do This section provides an activity which will

help you transfer your new knowledge or skill into real life situations or concerns.

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Assessment This is a task which aims to evaluate your

level of mastery in achieving the learning competency.

Additional Activities In this portion, another activity will be given

to you to enrich your knowledge or skill of the lesson learned. This also tends retention of learned concepts.

Answer Key This contains answers to all activities in the

module.

At the end of this module you will also find:

References This is a list of all sources used in developing this module.

The following are some reminders in using this module:

We hope that through this material, you will experience meaningful learning and gain deep understanding of the relevant competencies. You can do it!

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Week

What I Need to Know

This module was designed and written with you in mind. It is here to help you master the use of the other ingredients in cleaning agents. The scope of this module permits it to be used in many different learning situations. The language used recognizes the diverse vocabulary level of students. The lessons are arranged to follow the standard sequence of the course. But the order in which you read them can be changed to correspond with the textbook you are now using.

The module focuses on the use of the other ingredients in cleaning agents.

After going through this module, you are expected to give the use of the other ingredients in cleaning agents.

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What I Know

Direction: Write the chosen letter on a separate sheet of paper.

1. Aside from the active ingredient, there are also other ingredients included in cleaning agents. This ingredient helps in keeping the minerals out of the way of the surfactants. a. builders b. fragrance c. pH adjusters d. solvents

2. Depending on the chosen ingredient used in a product, what is the ingredient that helps to be more effective on certain microbes? a. antibacterial b. enzymes c. foam enhancer d. preservatives

3. Adding of this ingredient in a certain liquid cleaning agent will decrease the viscosity of the liquid. What is this ingredient? a. dye b. enzymes c. solvents d. thickener

4.Many people feel bubbles show that a product is working. What is the ingredient that creates suds in a cleaning agent? a. dye b. foam enhancer c. pH adjuster d. preservatives

5. What is the group of ingredients that came in a natural or synthetic compound which gives pleasant smell to the product? a. antibacterial b. foam enhancer c. fragrance d. thickener

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6. What ingredient has the power to break down stains like in digestive system which helps break down the food we eat? a. enzymes b. fragrance c. solvents d. thickener

7. This ingredient balanced the acidity or base of a certain product. What is this ingredient? a. dye b. fragrance c. pH adjuster d. solvents

8. What substance when added to a cleaning product makes it stable and safe for a longer period? a. enzymes b. foam enhancer c. pH adjuster d. preservative

9. What kind of ingredient is used in cleaning products that help in creating a unique experience? a. dye b. enzymes c. fragrance d. preservative 10. What is the pH of a certain product to be considered as basic? a. pH greater than 7 b. pH less than 7 c. average pH is 7 d. none of the above

11. What substance provides most of the cleaning power in cleaning products? a. antibacterial b. enzymes c. solvents d. surfactants

12. What are these ingredients included in a hand hygiene product which provides reduction in germs? a. antibacterial b. enzymes c. fragrance d. solvents

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13. This substance can be extracted in natural compounds. Which of the following is a natural compound? a. flowers b. fruits c. nuts d. all of the above

14. What substance helps the surfactant more powerful through the reaction of certain stuff which is found in tap water? a. antibacterial b. builders c. enzymes d. fragrance

15. Which of the following ingredients is considered as the active substance in a cleaning product? a. enzymes b. solvents c. surfactants d. thickener

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Lesson Use of the Other Ingredients 1 in Cleaning Agents

In cooking, there are many interpretations of some dishes. But when one or two ingredients are lacking, the food that you will eat will not be as delicious as what you expect. The same with the cleaning products. It is not only the active ingredient that plays an important role in cleaning agent but also the other ingredients.

What’s In

Cleaning products or agents are very helpful in maintaining our home a conducive place for relaxation. They can remove dirt, dust, bad odor, and other contaminants present in every corner of our home. They have different ingredients that suit to different cleaning products. Some can kill virus and bacteria while being able to clean an area. Others contain ingredients that can remove grease or oil on the surface. Most of the cleaning agents remove the foul odor in the surroundings.

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Notes to the Teacher Keep on reminding the learners to take extra careful in handling different cleaning products. They must choose wisely the products they will buy. They should purchase those eco-friendly products.

What’s New

Activity 1.1 “What’s that Word?” Cleaning products play an essential role in daily life. They can remove dirt and stains from our clothes, dried on food from our dishes and even germs from our hands! Let’s learn more about the chemistry that makes this happen. But before that let’s solve these jumbled words below to see what our next lesson will be.

Direction: Arrange the following jumbled letters to form the words related to cleaning agents/ingredients/products. 1. S N D H A 2. E A G S R E 3. I T D R 4. S V U R I 5. M U P F E RE 6. T A B E I A C R 7. E C N A L 8. U E H S O 9. L H T E H A 10. L A O H L C O 11. D I C A 12. G R D A E N 13. E G S A T R N M 14. O F R O L 15. T E T R E U X

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What is It

Uses of the Other Ingredients in Cleaning Products

With the different household cleaning products that we have in the market today, we don’t know which the best is to use in our household We assume that these cleaning products are safe to use. In fact, many popular household cleaners are dangerously toxic. They contain different ingredients that are harmful to our health Together with the active ingredient there are other ingredients found in cleaning agents. Let’s look at their uses.

1.Builders Builders are one of the important group of ingredients that help make cleaning products better. Builders give the surfactants a helping hand. They are found in several different kinds of products, but you need less of them than you do surfactants.

Builders help make the surfactant more powerful by reacting with stuff found in tap water. Water in your home may contain minerals (such as calcium and magnesium). The more minerals in your water, the “harder” the water is. It is not bad to have minerals in water, but it can leave white marks on surfaces (like dishes). When calcium and magnesium are present in water, they will stop surfactants from being able to do their job of removing soil.

Builders help prevent this by keeping the minerals out of the way of the surfactants. This leaves the surfactants alone to focus on the soil.

2. Solvents Solvents are chemicals that help ingredients stay mixed and gives cleaning products the right thickness, so they are easy to use. In addition, solvents can help to prevent liquid products from freezing in cold climates.

Without solvents, a product will be very thick. But for other products, we want the liquid to pour out of the bottle. When we add solvents, we decrease the viscosity, meaning the liquid will move faster when poured out of the bottle. The solvent also helps to makes sure we do not end up with a separated solution like when you have pulp at the bottom of your glass of orange juice.

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3. Enzymes Enzymes are powerful stain removing ingredients. Their power is to break down stains just like the enzymes in our digestive system help break down the food we eat. Enzymes are not living organisms but are created by naturally occurring microorganisms, like bacteria and fungi. In the laboratory, we use carefully selected microorganisms and allow them to grow in a very controlled environment. As they grow, they produce the desired enzymes.

4. Fragrances Fragrances are a group of ingredients that provide the cleaning product with a pleasant smell. They are not found in every product, and typically a very small amount can make a large difference in smell. In many cases, the fragrance is the driving factor for why someone decided to buy a specific product.

A fragrance is a mix of many different substances. These ingredients may be natural compounds (that come from materials like flowers, fruit, trees, plants, or nuts), essential oils, or synthetic compounds.

5.Preservatives Just like it is important to prevent food from spoiling, cleaning products need to be preserved as well. Adding a small amount of a preservative protects the product from microorganisms.

A preservative is a substance that is added to a cleaning product in order to make it stable and safe for a longer period. Without a preservative, it is possible for bacteria or fungi to grow in the product. This can cause the ingredients in the product (like surfactants and enzymes) to break down and not work as well. Adding a preservative allows a cleaning product to stay on the shelf longer both in the store and in your home.

6. pH Adjusters Every cleaning product needs to be “balanced” to work well and to be safe for your skin. In order to do this, chemists use pH adjusters to make sure the product is balanced and safe for you to use. The amount used depends on the other ingredients in the formula. pH is a measure of how acidic (like lemon juice) or basic (like baking soda) a solution is. One way to measure this is by using the pH scale. The pH scale is read from 0 to 14 and tells us if a solution is acidic or basic. Pure water has a pH of 7, which means it’s neutral.

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pH adjusters are used in cleaning products to raise or lower the pH of a solution, making it either more basic or acidic.

Chemists make sure that the product is effective while balancing safety, in part, by making sure the pH will not be harmful if it touches your skin.

If the pH is less than 7, then the solution is acidic. Lemon juice has a pH around 2. Our skin is slightly acidic, with a pH on average near 5. If our skin comes into contact with a chemical that is too acidic it can cause itching or discomfort.

Adjusting the pH helps to keep the product working well as it gets old. It also affects how the product cleans. For example, each surfactant has a different pH level in which they are the most powerful. Therefore, a chemist may want to adjust the pH to that level.

If the pH is greater than 7, then the solution is basic. For example, baking soda has a pH of around 9. If a solution is too alkaline (basic), it can also irritate your skin.

7.Dye There are several other ingredients used in cleaning products that help create a unique experience. For example, dye can be used to give a product color.

8. Thickener Thickeners give soap the proper viscosity (thickness), making sure it can still flow out of a bottle. Can you imagine trying to wash your hands with a soap that feels like water? It would run right off your skin!

9. Foam Enhancer Foam Enhancers help create suds or bubbles. While not necessary for effective cleaning, many people feel bubbles show that a product is working.

10. Antibacterial or Disinfecting Ingredients Cleaning washes away germs with any dirt and soil that is removed, but a further reduction of germs can be achieved by using additional ingredients that will kill germs.

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Antibacterial or disinfecting ingredients can be included in a cleaning or hand hygiene product or used separately after cleaning. Their use provides a further reduction in germs on our hands or surfaces in our homes. This reduction of germs helps to prevent people from getting sick when commonly used surfaces, such as door handles, or our hands are cleansed using these products. In environments with sick individuals or where food is prepared, this is especially important.

There are many different types of antibacterial or disinfecting ingredients. Depending on the chosen ingredient used in a product, it may be more effective on certain microbes that make us sick like bacteria, viruses or mold.

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What’s More

Activity 1.2 “A Powerful Tool” Direction: Make a short poem about the use of other ingredients found in household cleaning products incorporating your answers in Activity 1.1.

Rubrics Criteria Excellent Merit Achieved Needs Score (4pts) (3pts) (2pts) Improvement (1pt) Content Information Information Information Information is are clearly are clearly is clear unclear and presented presented written in Order of and ordered and ordered random order information in such a does not way that it clearly brings a full show picture of the material Creativity It is visually Visually Visually Readable inviting and inviting and pleasing easy to read easy to read and readable Spelling and All spelling Some Some Notable Grammar and spelling and spelling and spelling and grammar are grammar grammar grammar error correct error error Punctuality Submitted Submitted Submitted Submitted on time on time on time after the deadline TOTAL

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Highest possible score: (4x4)/4= 4 components Sample Score Sheet

Adjectival Rating

Criteria Score Learner is within the Merit range and Content 3 the teacher may choose a grade within Creativity 3 this range Spelling and Grammar 3

Punctuality 4

TOTAL 13

13 pts/4 categories= 3.25

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What I Have Learned

Activity 1.3 “Puzzled Ingredient” Direction: Find in the puzzle the given words below.

Adjuster Builders Enhancer Dye Enzyme Fragrance Disinfectant pH Preservative Solvents

E N H A N C E R T B S F S E A R B C N Y A U E R M O F I G H Z B X I J A

O C L C L M Y Z C L O G N P T V A S M D U D R R J S B D E R E V E E T A

U P E S W N S F T R Z N I H Y A I O T S G S B C C A D J U S T E R E J E D I S I N F E C T A N T P R E S E R V A T I V E

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What I Can Do

Activity 1.4 “A Safe Environment” Direction: With your knowledge on the different ingredients of cleaning products, make a poster on safe storage and use of the different cleaning agents. Write a short description of your work. Rubrics Criteria Excellent Merit Achieved Needs Score (4pts) (3pts) (2pts) Improvement (1pt) Content Information Information Information Information is are clearly are clearly is clear unclear and presented presented written in Order of and ordered and ordered random order information in such a does not way that it clearly brings a full show picture of the material Creativity It is visually Visually Visually Readable inviting and inviting and pleasing easy to read easy to read and readable Spelling and All spelling Some Some Notable Grammar and spelling spelling spelling and grammar are and and grammar error correct grammar grammar error error Punctuality Submitted Submitted Submitted Submitted on time on time on time after the deadline TOTAL Highest possible score: (4x4)/4= 4 components

Sample Score Sheet Adjectival Rating

Criteria Score Content 3 13 pts/4 categories= 3.25 Creativity 3 Learner is within the Merit range and Spelling and Grammar 3 the teacher may choose a grade within Punctuality 4 this range. TOTAL 13

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Assessment

Direction: Write the letter that match the different ingredients of cleaning agents with their uses. “Use of Different Ingredients” Use Ingredients 1. Washes away germs with any dirt A. Antibacterial 2. Give surfactants a helping hand B. Builders 3. Create suds or bubbles C. Dye 4.Give cleaning agents the right D. Enzymes thickness 5.Making the product balanced E. Foam enhancer 6.Powerful stain removing ingredient F. Fragrance 7.Protects products from G. pH microorganism 8. Provide product with a pleasant H. pH adjuster smell 9.Helps keep minerals out of way I. Preservatives 10.Prevents products from freezing J. Solvents 11.Mix of many different substances 12.Allows cleaning product to stay longer 13.Measures how a solution is acid or base 14.Helps create a new experience 15. Prevent people from getting sick

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Additional Activities

Activity 1.5 “Healthy Atmosphere” Direction: Read an article about the effectiveness of a cleaning agent in reducing the occurrence of diseases. Write your short opinion on a separate sheet of paper. Rubrics Criteria Excellent Merit Achieved Needs Score (4pts) (3pts) (2pts) Improvement (1pt) Content Information Information Information Information is are clearly are clearly is clear unclear and presented presented written in Order of and ordered and ordered random order information in such a does not way that it clearly brings a full show picture of the material Creativity It is visually Visually Visually Readable inviting and inviting and pleasing easy to read easy to read and readable Spelling and All spelling Some Some Notable Grammar and spelling and spelling and spelling and grammar are grammar grammar grammar error correct error error Punctuality Submitted Submitted Submitted Submitted on time on time on time after the deadline TOTAL Highest possible score: (4x4)/4= 4 components

Adjectival Rating Sample Score Sheet

Criteria Score Content 3 13 pts/4 categories= 3.25 Creativity 3 Spelling and 3 Learner is within the Merit range and Grammar the teacher may choose a grade within Punctuality 4 TOTAL 13 this range.s

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Answer Key

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. vary may Answer

Activities Additional

A 15.

C 14.

G 13.

I 12.

F 11.

J 10.

B 9.

F 8.

I 7.

D 6.

H 5.

J 4.

E 3. scoring.

B 2. for rubrics to Refer

A 1. . vary may s Answer

Assessment Do Can I What

TEXTURE 15. C 15.

FLOOR 14. B 14.

GARMENTS 13. D 13.

DANGER 12. A 12.

ACID 11. D 11.

ALCOHOL 10. A 10.

HEALTH 9. A 9.

HOUSE 8. D 8.

CLEAN 7. C 7.

BACTERIA 6. A 6.

PERFUME 5. C 5.

VIRUS 4. B 4.

scoring. DIRT 3. C 3.

Refer to rubrics for for rubrics to Refer GREASE 2. A 2.

vary. may s Answer HANDS 1. A 1.

More What's New What’s Know I What

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What I Have Learned

E V I T A V R E S E R P

T N A T C E F N I S I D

E J E R E T S U J D A C

C B S G S T O I A Y H I

N Z R T F S N W S E P U

A T E E V E R E D B S J

R R D U D M S A V T P N

G O L C Z Y M L C L C O

A J I X B Z H G I F O M

R E U A Y N C B R A E S

F S B T R E C N A H N E

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References

Website:

“Baking Soda”, Accessed July 21, 2020, https://oconto.extension.wisc.edu/files /2011/02/Baking-Soda.pdf#:~:text=Cleaning%3A%20Baking%20Soda%20 acts%20a%20cleaning%20agent%20because,for%20easy%20removal%20as %20a%20gentle%20scouring%20powder.

“Ingredients”, Accessed July 22, 2020, https://explorationclean.org/ingredients

Commission on Higher Education. Teaching Guide for Senior High School: Physical Science.Book.https://drive.google.com/file/d/0B869YF0KEHr7SHFGVG5m VFFhcXc/view. Creative Commons Attribution-NonCommercial-ShareAlike 4.0

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For inquiries or feedback, please write or call:

Department of Education - Bureau of Learning Resources (DepEd-BLR)

Ground Floor, Bonifacio Bldg., DepEd Complex Meralco Avenue, Pasig City, Philippines 1600

Telefax: (632) 8634-1072; 8634-1054; 8631-4985

Email Address: [email protected] * [email protected]

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