Chemical Changes and Counting Atoms

COUNTING ATOMS

SWBAT: Understand fully how to calculate atoms in a chemical formula, know reactants vs Products, and identify molecules.

​Reactants are molecules that will mix together or separate (making chemical bonds together) which will create new Molecules (products)

REACTANTS VS PRODUCTS

Communicating why you are angry

Multiple Choice

Which of these is the Product?

• 2 Na + Cl₂

• 2NaCl

• This equation does not contain a product

• This equation needs a reactant before a product is produced

Multiple Choice

Which one is the reactants?

• The left side of the arrow

• The molecule of water on the right side of the arrow

• The arrow itself signifies the reactants

• There is no reactant present in the chemical formula

​Atoms- (smallest unit of mass of an element)

ELEMENTS- They are the letters (Capitalized letters) when you see an uppercase with a lowercase they are together
MOLECULES - When there is more than one atom per element it is called a molecule (see the coefficient)

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-Atoms
-Elements
-Molecules

Multiple Choice

How many molecules does water have?

• 2 molecules of water represented by the Coefficient (big number)

• 2 Molecules of water are represented by the subscript(small number next to H

• There is 1 molecule of water

• There is only 1 molecules because there is only one Oxygen atom

Multiple Choice

How many molecules of Hydrogen?

• One because there is only one element

• 3 molecules because the coefficient is 3

• 2 molecules because there is a 2 next to H

• none

Remember to use a T chart to separate the elements and the atoms.

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Lets try it.

​Expert at counting atoms

Multiple Choice

Tell me how many Atoms in total are in this molecule?

• 13 atoms in total

• 16 atoms in total

• 10 atoms in total

• 3 atoms in total

Multiple Choice

How many elements does this molecule have?

• 2

• 3

• 10

• 14

Multiple Choice

How many Oxygen are in H₂O?

• 1
• 2
• 0
• 4

Multiple Choice

How many molecules in 4H₂O ?

• 4

• 5

• 2

• 9

Multiple Choice

How many elements are in C₆H₁₂O₆?

• 1
• 2
• 3
• 4

1. Work on the paper you grabbed from the DO NOW bin.

2. Any questions raise your hand

3. During this study session, there is no talking (Voice Level 0)

4. You may use your notes or google to help you answer questions.

5. you will have 15 min to work on this.
   
   

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Work on review

​Extra Work Practice!