1. Mole Triangle Review Begin Stoichiometry
Chemistry GT 3/5/15

2. Drill How many moles are equivalent to:
450. g Ca(OH)2
935.2 g zinc chloride
HW: Mole-Mole/Mass-Mass WS (finish)

3. Objectives IWBAT Convert from moles to grams and back
Convert from moles to units and back
Convert from moles to liters and back
Use the mole triangle to do two step conversions

4. Mole Triangle We can convert between Ms. Bloedorn will show you how! 
Mol  g and back
mol  particle and back
mol  L and back
Ms. Bloedorn will show you how! 

5. Stoichiometry
The study of quantitative relationships between amounts of reactants used and products formed by a chemical reaction

6. What’s going on here?
The candle burns freely in air, but what happens when it is covered with a beaker?
smothered, goes out
What fuel runs out first?
oxygen runs out

7. Mole Chemical Relationships
Mole-Mass Relationships in Chemical Reactions:
Law of Conservation of Mass:
Mass cannot be created or destroyed by ordinary chemical changes
Look at:
Fe(s) + O2(g)  Fe2O3(s)
Is it balanced? If not, balance it.
4 Fe(s) + 3 O2(g)  2 Fe2O3(s)

8. Interpret the equation
Iron + oxygen  Iron (III) oxide
4Fe(s) + 3O2(g)  2Fe2O3(s)
4 atoms Fe + 3 molecules O2  2 molecules Fe2O3
4 mol Fe + 3 mol O2  2 mol Fe2O3
223.4 g Fe g O2  g Fe2O3
These all tell you different information, but also represent the same reaction.

9. Stoichiometric Calculations
1/2 cup butter
1/2 cup brown sugar
1/2 cup granulated sugar
1 egg
1/2 teaspoon vanilla
1 cup all-purpose flour
1/2 teaspoon salt
1/2 teaspoon baking soda
1/2 cup semisweet chocolate chips
Makes 42 cookies.
What is the product of this chemical reaction?
42 cookies
How would you adjust the ingredients to make seven dozen cookies?
Make twice as much (7 x 6, then 7 x 12)

10. The Mole “Bridge” moles of B moles of A Moles of A Moles of B
# grams B
1 mol B
1 mol A
# grams A
Grams of A
Grams of B
*** You MUST have a balanced equation! ***

11. Stoichiometry Conversion Flowchart wA + xB  yC + zD
Liters A
Liters B
22.4L B
1 mol B
1 mol B
22.4L B
22.4L A
1 mol A
1 mol A
22.4L A
1 mol B
6.022 x 1023 units B
6.022 x 1023 units A
1 mol A
w mol A
x mol B
Atoms/ units B
Atoms/ units A
mol B
mol A
1 mol A
6.022 x 1023 units A
x mol B
w mol A
1 mol B
Molar mass B
6.022 x 1023 units B
1 mol B
Molar mass g B
1 mol B
1 mol A
Molar mass A
Molar mass g A
1 mol A
grams A
grams B

12. Stoich. Calculations, cont.
Sometimes, a chemist needs to make a certain amount of a product, or only has a certain amount of a starting material. How much reactant should be used? How much product will be made?
ex. How many moles of hydrogen will be produced when mol potassium react with water?
2K(s) + 2H2O(l)  2KOH(aq) + H2(g)
mol K • 1 mol H2 = mol H2
2 mol K

13. Mass to Mass Conversion
Ammonium nitrate (NH4NO3) decomposes into N2O and water. Determine the mass of water produced from the decomposition of 25.0 g solid ammonium nitrate.
NH4NO3  N2O + 2H2O
25.0 g NH4NO3 • 1 mol NH4NO3 • 2 mol H2O • g H2O = 11.3 g H2O
80.04 g NH4NO3 1 mol NH4NO mol H2O

14. Practice
Start on Mole-Mole side of WS
Then, Mass-Mass side of WS

15. Closure
Calculate, in 2.3 mol Na3PO4,
How many grams?