Stoichiometry Test Review Answers
Objectives:
Given a reaction (described in words), be able to start with at any of the three starting points on the
flow chart (mass A, volume A(aq), volume A(g)) and calculate any of the four possible outcomes of
the flow chart (mass B, volume B(aq), volume B(g), molarity B).
Use multiple amounts of starting materials to determine the substance that is limiting reagent and the
amount of product that can be produced based on that limiting reagent.
Practice Problems:
1. How many grams of water can be produced by the combustion of propane (C3H8) in 8.34g of
oxygen to form carbon dioxide and water? 3.76g H2O
2. How many mL of 6.00M sulfuric acid can be neutralized by the reaction with 27.89g sodium
hydrogen carbonate to form sodium sulfate, water, and carbon dioxide? 27.7mL H2SO4
3. How many L of oxygen gas at STP can be produced by the decomposition of 45.6g of
potassium chlorate to form potassium chloride and oxygen? 12.5L O2
4. It takes 6.50g of potassium carbonate to completely neutralize 15.0mL of hydrochloric acid
with unknown concentration. If the reaction produces potassium chloride, water and carbon
dioxide, then what is the molarity of the hydrochloric acid? 6.27M – remember to stop at
moles and do the separate algebra step for molarity
5. What mass of barium hydroxide is required to neutralize 30.0mL of 0.100M hydrochloric
acid to produce barium chloride and water? 0.257g Ba(OH)2
6. What volume in mL of 0.600M sodium hydroxide is required to react with 15.0mL of
0.500M iron(III) nitrate to form iron(III) hydroxide precipitate and sodium nitrate?
37.5mL NaOH
7. How many liters of carbon dioxide gas are produced at STP by the reaction of 85.0mL of
0.500M acetic acid and excess sodium carbonate if water and sodium acetate are also
produced? 0.476L CO2 - start with liquid volume of acetic acid to mol acetic acid and
then go to mol CO2 and then to gas volume
8. 20.0mL of an unknown concentration sodium hydroxide is titrated with 15.89mL of 0.250M
sulfuric acid to produce sodium sulfate and water. What is the molarity of the sodium
hydroxide? 0.397M – remember to stop at moles and do the separate algebra step for
molarity
9. If 5.91 L of oxygen at STP is needed, how many grams of hydrogen peroxide (H2O2) must be
decomposed to form oxygen and water? 17.9g H2O2
10. One problem with sodium hydroxide solutions is that they react with carbon dioxide in the
atmosphere to form sodium carbonate and water. How many milliliters of 0.500M sodium
hydroxide will be neutralized by the reaction with 4.90L of CO2 at STP? 875mLNaOH
11. How many L of hydrogen gas are required to react with 4.5L of nitrogen gas to produce
ammonia at STP? 14L H2 – watch sig figs!
12. It takes 56.98mL of sulfuric acid of unknown concentration to react with sodium hydrogen
carbonate to produce sodium sulfate, water, and 19.0L of carbon dioxide at STP. What is the
molarity of sulfuric acid? 7.44M – remember to stop at moles and do the separate algebra
step for molarity