Stoichiometry Review
1. Iron reacts with oxygen to produce iron (III) oxide. If 74.9 g of iron is used, what mass of
oxygen is needed for the complete reaction?
4Fe + 3O2 → 2Fe2O3
2. A 20.3 g sample of Mg(OH)2 is reacted with 12.0 g of HCl according to the reaction:
Mg(OH)2 + 2HCl  MgCl2 + 2H2O
How much H2O is produced?
3. At high temperatures, sulfur combines with Iron to form the brown-black iron (II) sulfide:
Fe + S  FeS
In one experiment, 9.62 g of Fe are allowed to react with 8.67 g of S.
a. What is the limiting reagent?
b. Calculate the mass of FeS formed.
4. In lab we made calcium carbonate by mixing 2.5 g of calcium chloride with 3.2 g of
sodium carbonate.
a. Write a balanced chemical equation for this reaction
b. Determine how many grams of calcium carbonate can be formed.
c. In the lab the actual amount of calcium carbonate that was formed was 1.41 g,
determine the percent yield for this experiment.
5. Balanced Equation: C2H4 + 3O2  2CO2 + 2H2O
Type of Reaction: ___________________
How many moles of O2 would be needed to react with 2.5 moles of C2H4 ?
Type of Stoich conversion____________________
6. How many moles of C2H4 would be needed to react with 15.4 grams of O2?
Type of Stoich conversion____________________
7. How many grams of CO2 would be produced from 16.7 moles of O2?
Type of Stoich conversion____________________
Vocab
1. Coefficient
2. Subscript
3. Reactant
4. Product
5. Moles
6. Mole ratio
7. Theoretical yield
8. Percent yield
9. Limiting reactant
10. Law of conservation of matter