Unit 3: Chemistry Day 2 – Elements vs. Compounds

Unit Essential Questions: Vocabulary: SWBAT 1. What is the smallest part of an element?  Element  … identify that a substance is a compound 2. How are atoms and elements related?  Compound 3. How do scientists use density to identify by its chemical formula, absence on the substances?  Chemical Formula Periodic Table, and that it contains two or  Periodic Table of Elements more types of atoms.

Video: Guiding Questions

1. How many elements need to combine in order to form a compound? 3. H2O is the chemical formula for what?

2. What is the recipe for a compound called? 4. What elements are present in water?

5. What is another compound the video talks about?

GUIDED NOTES: Elements and Compounds

Homework: Finish entire packet. STOP AND JOT: What is the difference between an element and a compound?

Chemical Formulas

 Compounds are represented by ______.  Each capital letter represents ______element.  ______represent the number of atoms of each element.

Examples: H2O Si3N4  Number of elements: ______ Number of elements: ______ Number of atoms for each element:  Number of atoms for each element: ______

How many elements are in How many atoms of each How many elements are in How many atoms of each the compound H3PO4? element is present in the the compound C2H5OH? element is present in the compound, HNO3? compound, C2H4O2?

Three ways to identify a Compound:

1. Made of more than one ______. 2. Not located on the ______. 3. Represented by a ______.

Homework: Finish entire packet. INDPENDENT PRACTICE:

DIRECTIONS: Answer each question below. You may use your notes and textbook for help.

How many elements are in the Circle the compound. How many atoms are present in the Is Nitric Acid – HNO3 considered an chemical formula below? element Silicon from the chemical element? Why or why not? If not,  Carbon Dioxide formula? what is it? HSiNeK2  Helium  Potassium Si4HeO2  Boron How do you know? List the names of the elements. How do you know?

Circle the compound. How many atoms are present in the Is Iridium – Ir considered a How many elements are in the element Hydrogen from the compound? Why or why not? If not, chemical formula below?  Fe chemical formula? what is it?  K C2H4O2C  H2O C3H6O  Mg

List the names of the elements. How do you know? How do you know?

Is Sulfuric Acid – H2SO4 considered a How many elements are in the Circle the compound. How many atoms are present in the compound? Why or why not? If not, chemical formula below? element Oxygen from the chemical what is it?  NaCl formula? CH3OH  Li  B H2SO4 List the names of the elements.

How do you know? How do you know?

How many atoms are present in the Is Gallium – Ga considered an How many elements are in the Circle the compound. element Phosphorous from the element? Why or why not? If not, chemical formula below? chemical formula? what is it?  Mn NeO2HFeOHLi2  Hg H3PO4  NaOH

List the names of the elements. How do you know? How do you know?

Homework: Finish entire packet.

INDEPENDENT PRACTICE: Complete the WYKAT below.

WYKATW H A T Y O U K N O W A B O U T T H A T

1 What are the three ways to identify an 2 What are the three ways to identify a 3 Write the element name/chemical element? compound? symbol for the following: 3

1. 1. 3 Potassium

2. 2. Fe

Iodine 3. 3. O

Gallium

4 The diagrams below illustrate models of various chemical compounds. A new compound has just been made. 5 Its formula is:

CoN2FeBOH

How many different elements make up this compound?

List all the elements in this compound below. The diagrams suggest that compounds must be

A. Made up of oxygen and one other element. B. Made up of two or more chemical elements. C. Made up of two or more of the same chemicals only. D. Made up of only one chemical element.

Homework: Finish entire packet.