1. It’s time to learn about . . .
the Mole ! 1

2. Stoichiometry

3. Stoichiometry : Mole Ratios to
Stoichiometry : Mole Ratios to Determining Grams of Product At the conclusion of our time together, you should be able to:
Review the conversion of particles or grams to moles
Determine mole ratios from a balanced chemical equation
Determine the amount of product produced when given the amount of reactants

4. Review the Molar Mass of Compounds
The molar mass (MM) of a compound is determined by adding up all the atomic masses for the molecule (or compound)
Ex. Molar mass of CaCl2
Avg. Atomic mass of Calcium = 40.08g
Avg. Atomic mass of Chlorine = 35.45g
Molar Mass of calcium chloride = g/mol Ca + (2 X 35.45) g/mol Cl  g/mol CaCl2 20
Ca 
17 Cl 35.45

5. Practice Calculate the Molar Mass of calcium phosphate Formula =
Masses elements:
Molar Mass = g
Ca3(PO4)2

6. Calculations
molar mass Avogadro’s number Grams Moles Particles Everything must go through Moles!!!

7. Flowchart Atoms or Molecules Moles Mass (grams) Divide by 6.02 X 1023
Multiply by
6.02 X 1023
Multiply by atomic/molar mass from periodic table
Moles
Divide by atomic/molar mass from periodic table
Mass (grams)

8. “Mole Relationships” Lab – Page 9
Lead (II) nitrate and sodium iodide  ????
Which test tube will produce the max amount?
Test #1
Test #2
Test #3
Test #4
Test #5
1.5:4.5
2:4
3:3
4:2
4.5:1.5

9. Chocolate Chip Cookies!!
1 cup butter 2 eggs 1/2 cup white sugar 1 teaspoon salt 1 cup packed brown sugar 1 teaspoon vanilla extract 2 1/2 cups all-purpose flour 1 teaspoon baking soda 2 cups semisweet chocolate chips Makes 3 dozen
How many eggs are needed to make 3 dozen cookies?
How much butter is needed for the amount of chocolate chips used?
How much brown sugar would I need if I had 1½ cups white sugar?

10. Cookies and Chemistry…Huh!?!?
Just like chocolate chip cookies have recipes, chemists have recipes as well
Instead of calling them recipes, we call them reaction/equations
Furthermore, instead of using cups and teaspoons, we use moles
Lastly, instead of eggs, butter, sugar, etc. we use chemical compounds as ingredients

11. Mole Ratios
These mole ratios can be used to calculate the moles of one chemical from the given amount of a different chemical
Are obtained by comparing the coefficients in a balanced chemical equation.

12. Chemistry Recipes
Looking at a reaction tells us how much of something you need to react with something else to get a product (like the cookie recipe)
Be sure you have a balanced reaction before you start!
_SiO2 + _HF  _SiF4 + _H2O
Mole Ratios
SiO2 to SiF4 SiF4 to H2O H2O to HF SiO2 to HF

13. 25 moles of SiO2 converts to:
Practice – Page 11
25 moles of SiO2 converts to:
Moles of SiF4?
Grams of SiO2?
Molecules of SiF4?

14. 5.0 moles of Ag converts to:
Practice – Page 11
_Ag + _Cl2 +  _AgCl
5.0 moles of Ag converts to:
Moles of Cl2?
Grams of Cl2?

15. Mass-Mass Conversions – Page 13
Most often we are given a starting mass and want to find out the mass of a product we will get (called theoretical yield) or how much of another reactant we need to completely react with it (no leftover ingredients!)
Now we must go from grams to moles, to mole ratios, and back to grams of the compound we are interested in.

16. Mass-Mass Conversion – Page 13
Calculate how many grams of iron are required to make 86.7g of FeS? __Fe + __S8  __FeS

17. Practice Mass-Mole-Mass – Page 13 #2
If 17.6g of carbon disulfide react with an excess of chlorine, how many grams of disulfur dichloride will result?

18. Stoichiometry : Mole Ratios to
Stoichiometry : Mole Ratios to Determining Grams of Product Let’s see if you can:
Review the conversion of particles or grams to moles
Determine mole ratios from a balanced chemical equation
Determine the amount of product produced when given the amount of reactants

19. Mass-Mole-Molecules: Determine the number of molecules in 73 g of water
# H2O molecules =
73 g H2O
x 1 mol H2O
18.02 g H2O
x 6.02x1023 molecules
1 mol H2O
= 2.4 x 1024 molecules H2O

20. Try this one:
Calculate the mass in grams of iodine required to react completely with 0.50 moles of aluminum.
Al + I2  AlI3
2 Al + 3 I2  2 AlI3
x 3 mol I2
2 mol Al
0.50 mol Al
x g I2
1 mol I2
= 190 g I2

21. Try this one:
Calculate the mass in grams of iodine required to react completely with 0.50 g of aluminum.
Al + I2  AlI3
2 Al + 3 I2  2 AlI3
x 1 mol Al
26.98 g Al
0.50 g Al
x 3 mol I2
2 mol Al
x g I2
1 mol I2
= 7.1 g I2