Chemistry Scavenger Hunt

Pre-AP Chemistry Unit 3 HW Packet LEGGETT Name ______WKS 3.1 - Classifying Matter (2 pages)

Answer the questions based on the model below.

1. Which substance(s) shown would be considered a compound?

2. Which substance(s) shown would be considered an atom/element?

3. Does the diagram represent a pure substance, homogeneous mixture, or heterogeneous mixture? Give a reason to support your answer.

Answer each of the questions below based on the models below. There can be more than one answer for each.

4. Which model(s) show pure substances?

5. Which model(s) show mixtures?

6. Which model(s) show a single type of atom/element?

7. Which model(s) show a mixture of compounds and elements?

8. Which model(s) show a single type of compound?

9. Which model(s) show a mixture of different elements?

10. Which model(s) show a mixture of different compounds?

11. For each type of mixture below, draw a picture representing the size and distribution of particles in a liquid.

SOLUTION COLLOID SUSPENSION Page 1 of 10 Pre-AP Chemistry Unit 3 HW Packet Name ______WKS 3.1 - Classifying Matter (continued) State whether each of the following is a homogeneous mixture, heterogeneous mixture, compound, or an element. Explain how you made your decision in each case. Element, Compound, Homogeneous Explanation supporting decision Mixture, or Heterogeneous Mixture 1 hydrogen 2. 1 table salt 3. 1 sugar water 4. 1 carbon dioxide 5. 1 ketchup 6. 1 pure air 7. 1 pure water 8. 1 tap water 9. 2 70% rubbing 0. alcohol solution 2 iron 1. 2 rocky road ice 2. cream

23. How can one tell the difference between a colloid and suspension?

24. How can one tell the difference between a solution and a colloid?

25. What are some examples of physical separation?

26. Compare and contrast a mixture and a compound. How are they alike? How are they different?

of 10 Pre-AP Chemistry Unit 3 HW Packet Name ______27. A chemist heats some white crystals in a test tube. The crystals make a cracking sound, fall apart into smaller pieces, and give off a misty gas. A colorless liquid forms around the cooler top of the test tube. Tell whether you think the original crystals were a compound or an element, and why.

WKS 3.2 – Chemical vs. Physical Properties (1 page) Classify the following properties as either chemical or physical and then justify your answer with an explanation. Physical or Explanation supporting your decision Chemical Property? 1. Blue color

2. Density

3. Flammability

4. Solubility

5. Reacts with acid to form H2

6. Supports combustion

7. Odor

8. Melting point 9. Reacts with water to form a gas 10. Luster

11. Boiling point

12. Can neutralize a base

Physical properties can be further broken down into two types – INTENSIVE & EXTENSIVE. Be sure to write out the whole word. It will be VERY helpful to you in the future to know this because IF a property is INTENSIVE, then we can safely assume any convenient amount we want! Intensive or Extensive? Explanation supporting your decision 13. Mass 14. Number of atoms 15. Color 16. Odor 17. Melting point 18. Density 19. Malleability

of 10 Pre-AP Chemistry Unit 3 HW Packet Name ______20. Volume 21. Length 22. Electrical Conductivity WKS 3.3 – Chemical vs. Physical Changes (1 page) In a physical change, the original substance still exists. It has only changed in form. In a chemical change, a new substance is produced. Classify the following as being a physical or chemical change. If it is chemical, state what evidence(s) of a chemical change would be seen in the example. 1. Sodium hydroxide dissolves in water. ______

2. Hydrochloric acid reacts with potassium hydroxide to produce a salt, water and heat. ______

3. A pellet of sodium is sliced in two. ______

4. Water is heated and changed to steam. ______

5. Potassium chlorate decomposes to potassium chloride and oxygen gas. ______

6. Iron rusts. ______

7. When placed in H2O, a sodium pellet catches on fire as hydrogen gas is liberated and sodium hydroxide forms. ______

8. Evaporation. ______

9. Ice melting. ______

10. Sugar dissolves in water. ______

11. Wood rotting. ______

12. A tire is inflated with air. ______

13. Food is digested by hydrochloric acid in the stomach. ______

14. Water is absorbed by a paper towel. ______

15. Breaking a piece of glass with a hammer. ______

16. Milk is left outside of a refrigerator for seven months and spoils. ______

17. Dew forms on trees leaves from condensation. ______

18. Water is purified by a process of filtration. ______

19. Leaves changing color in the autumn. ______

20. A student fries an egg for a yummy breakfast. ______

21. Fermenting of wine from grapes. ______Page 4 of 10 Pre-AP Chemistry Unit 3 HW Packet Name ______

22. Burning wood. ______

23. Silver tarnishing. ______

of 10 Pre-AP Chemistry Unit 3 HW Packet Name ______WKS 3.4 – States of Matter (2 pages) 1. What are the differences between intramolecular bonding and intermolecular forces?

2. For each of the following, indicate if it represents a solid, liquid, or gas. SOLID LIQUID GAS Definite volume, definite shape Molecules organized in set pattern Molecules far apart Least dense Strongest intermolecular interactions Diffuses an immeasurable amount Easily compressed Definite volume, no definite shape Incompressible Diffuse easily but slowly Most dense Molecules close, but have free motion No intermolecular interactions No definite shape, no definite volume Vibrations only of molecules Diffuse easily and quickly

3. Match the pictures with the following descriptions.

 Diatomic Gas  Liquid  Solid  Liquid with Diatomic Gas

4. Compare and contrast the motion of particles of solids, liquids, and gases.

5. Gases and liquid are both fluids; they can flow. What is different about the intermolecular forces of attraction between the phases that allows fluids and gases to flow, but prevent solids from flowing?

of 10 Pre-AP Chemistry Unit 3 HW Packet Name ______WKS 3.4 – States of Matter (continued) 6. For each phase transition listed in the center column, draw and arrow from the beginning phase, through the transition, to the ending phase. The first is done for you.

Gas Sublime Gas Freeze Liquid Vaporize Liquid Condense Solid Deposition Solid Melt

7. For each of the six phase changes, which ones are considered endothermic (taking in heat)?

8. Which phase changes are considered exothermic (releasing heat)?

9. Why do ice cubes shrink if left in the freezer for a long time? Why do moth balls & solid air fresheners disappear over time? How do you know? (Hint: the same thing is happening in all of the cases.)

10. Energy is added to a solid substance at a constant rate. The temperature of the substance rises for a while, but a point is reached at which the temperature does not rise. At this point, what is happening to the substance? Describe what is happening to the energy being supplied to the solid during this time.

11. Distinguish between evaporation and vaporization.

12. Are phase changes considered physical or chemical changes? WHY???

of 10 Pre-AP Chemistry Unit 3 HW Packet Name ______WKS 3.5 – Heating/Cooling Curves (1 page) The graph below shows a pure substance which is heated by a constant source of heat. Identify the area described in the questions below by using the letters from the graph.

1. Being warmed as a solid ______10. Where do the molecules have the highest kinetic 2. Being warmed as a liquid ______energy? ______3. Being warmed as a gas ______11. What happened to the temperature during a phase 4. Changing from a solid to a liquid ______change? WHY? 5. Changing from a liquid to a gas ______6. States present from V to W? ______7. Sates present from X to Y? ______8. What is its boiling temperature? ______9. What is its melting temperature? ______======12. Construct a heating/cooling curve for Mercury (Hg). Mercury has a boiling point of 356.73˚C and a freezing point of –38.83˚C. Be sure to label the x and y axis, and label the melting & boiling points on the temperature axis.

======Identify the following phase transition and write it on the first line. On the second line, indicate whether energy belongs on the product side or the reactant side of the equation. Phase transition Energy side

13. ______, ______CH3CH2OH (l)  CH3CH2OH (g)

14. ______, ______Al (l)  Al (s)

15. ______, ______I2 (s)  I2 (g)

16. ______, ______W (s)  W (l)

17. ______, ______N2 (g)  N2 (l) Page 8 of 10 Pre-AP Chemistry Unit 3 HW Packet Name ______WKS 3.6 – Phase Diagram (1 page) Answer the following questions regarding the phase diagram of ammonia.

111.5 ) m t a (

u 1.0 s s e r P 0.05997

195.42 239.8 405.38 Temperature (K)

1. Label the solid, liquid, and gas phases on the above chart.

2. Use arrows to label and indicate the following phase changes on the graph above: a. Melting d. Condensation b. Freezing e. Sublimation c. Vaporization f. Deposition

3. What are the pressure and temperature conditons of the triple point of ammonia? ______

4. What phase(s) are present at the triple point? ______

5. If ammonia is compressed from 0.005 atm to 0.995 atm at a constant temperature of 230 K, what phase

change is observed? ______

6. If ammonia heated from 25 K to 195.42 K at a constant pressure of 0.025 atm, what phase change is

observed? ______

7. If a substance’s pressure and temperature are found to fall “on the line”, we would say that substance is in a phase equilibrium. What is the definition of equilibrium?

of 10 Pre-AP Chemistry Unit 3 HW Packet Name ______WKS 3.7 – Review – Part One (1 page) 1. Identify each of the following as intensive or extensive. a. melting point ______c. density ______b. mass ______d. length ______

2. Classify each of the following as a physical property (PP) or a chemical property (CP). a. aluminum has a silvery color ______d. water boils at 100°C ______b. gold has a density of 19.3 g/cm3 ______e. sodium ignites when dropped in water ______c. silver tarnishes ______f. mercury is a liquid at room temperature ______3. Classify each of the following as a physical change (PC) or a chemical change (CC). a. breaking a pencil in two ______d. burning wood ______b. water freezing and forming ice ______e. leaves turning color in the fall ______c. frying an egg ______f. water evaporating ______4. List the indicators that would let you know a chemical change has probably taken place.

5. For the three processes modeled below, state for each if a physical or chemical change is occurring.

6. Describe the difference between a chemical change and a physical change.

7. "A mixture is a chemical bonding of two or more substances in any proportion". Is this statement true or false? EXPLAIN!

8. Can two different samples of the same substance have different physical properties? Explain and give examples.

of 10 Pre-AP Chemistry Unit 3 HW Packet Name ______WKS 3.8 – Review – Part Two (1 page) 1. Describe how a homogeneous mixture differs from a heterogeneous mixture.

2. Describe how you could identify a homogeneous mixture from a heterogeneous mixture.

3. Describe how you could identify a colloid from a suspension.

2. Identify each of the following as an example of a physical property (PP) or a chemical property (CP).

a. Silver tarnishes when it comes in contact with hydrogen sulfide in the air ______b. A sheet of copper can be pounded into a bowl. ______c. Barium melts at 725°C. ______d. Helium does not react with any other element. ______e. A bar of lead is more easily bent than is a bar of aluminum of the same size. ______f. Potassium metal is kept submerged in oil to prevent contact with oxygen or water. ______g. Diamond dust can be used to cut or grind most other materials. ______

3. Identify each of the following as a property of a solid, liquid, or gas. Some answers will include more than one state of matter. a. flows and takes the shape of its container ______b. compressible ______c. made of particles held in a specific arrangement ______d. has a definite volume ______e. always occupies the entire space of its container ______f. has a definite volume but flows ______

4. Identify each of the following as an example of a element (ELE), a compound (COMP), homogeneous mixture (HOM) or a heterogeneous mixture (HET). a. 70% isopropyl rubbing alcohol ______h. salt water ______b. aluminum foil ______i. concrete ______c. gasoline ______j. bread ______d. sucrose (table sugar) ______k. rust ______e. a diamond (diamonds are carbon!) ______l. hydrogen ______f. fruit salad ______m. air in a balloon ______

of 10 Pre-AP Chemistry Unit 3 HW Packet Name ______g. carbon dioxide ______n. dirt ______