1. Stochiometry

2. C6H12O6(s) + 6O2(g)  6CO2(g) + 6 H2O(g)
What do the coefficients mean?
Ratio of reactants and products

3. Think of it like….. A recipe: all these together makes 60 cookies
2 1/4 cups all-purpose flour
1 teaspoon baking soda
1 teaspoon salt
1 cup (2 sticks) butter, softened
1 ½ cup packed brown sugar
1 teaspoon vanilla extract
2 large eggs
2 cups (12-oz. pkg.) NESTLÉ® TOLL HOUSE® Semi-Sweet Chocolate Morsels

4. So what if you want to make 90 cookies?
2.25 F + 1 NaHCO3 +1 NaCl + 1 B+.75 BS + 1V + 2E + 2 CC = 60 Ck

5. How to solve stoichiometry
Balance
Use mole ratios to find moles needed
C6H12O6(s) + 6O2(g)  6CO2(g) + 6 H2O(g)

6. How to solve stoichiometry
Balance
Use mole ratios to find moles needed
C6H12O6(s) + 6O2(g)  6CO2(g) + 6 H2O(g)
For every 1 mole of glucose, 6 moles of oxygen must be burned, so if you have
2 mole C6H12O6 : 1mole C6H12O6 as
x mole O2 :6 moles O2

7. Stoichiometry: Mole-Mole Problems
N2 + 3H2 → 2NH3
 How many moles of hydrogen, H2, are needed to react with 2.0 moles of nitrogen, N2?

8.  2KClO3 → 2KCl + 3O2
How many moles of oxygen are produced by the decomposition of 6.0 moles of potassium chlorate, KClO3?

9. Zn + 2HCl → ZnCl2 + H2
How many moles of hydrogen are produced from the reaction of 3.0 moles of zinc?

10. C3H8 + 3O2 → 3CO2 + 4H2
 How many moles of oxygen are necessary to react completely with 4.0 moles of propane (C3H8)?

11. K3PO4 + Al(NO3)3 → 3KNO3 + AlPO4
How many moles of potassium nitrate are produced when 2.5 moles of potassium phosphate react?

12. What about Mass???? But what about mass?
We have to change mass to moles before doing any ratio comparison. I think of it as a bridge. To get on the bridge, you change from grams to moles. To get off the bridge you change back.

13. Mole bridge

14. N2 + 3H2 → 2NH3
 How many grams of hydrogen, H2, are needed to react with 6.0 grams of nitrogen, N2?

15. 2KClO3 → 2KCl + 3O2
How many grams of oxygen are produced by the decomposition of 6.0 grams of potassium chlorate, KClO3?

16. Zn + 2HCl → ZnCl2 + H2
How many grams of hydrogen are produced from the reaction of 3.0 gramsof zinc?

17. C3H8 + 3O2 → 3CO2 + 4H2
 How many grams of oxygen are necessary to react completely with 4.0 grams of propane (C3H8)?

18. K3PO4 + Al(NO3)3 → 3KNO3 + AlPO4
How many moles of potassium nitrate are produced when 2.5 moles of potassium phosphate react?