Homework: Limiting Reactant
and Percent Yield

Show work for all calculations. You will need a calculator and a periodic table to complete them. You may also use your ions reference sheet.

1. A manufacturer of bicycles has 4,815 wheels, 2,305 frames, and 2,225 handlebars.
   1. How many bicycles can be manufactured using these parts?
   2. How many parts of each kind are left over?
   3. Which part limits the production of bicycles?
2. 2NaOH + CO₂ → Na₂CO₃ + H₂O
   Sodium hydroxide reacts with carbon dioxide to make sodium carbonate and water. Which reactant is limiting when 1.85 mol sodium hydroxide and 1.00 mol carbon dioxide are allowed to react? How many moles of sodium carbonate are produced? How many moles of the excess reactant remain after the reaction is complete?
3. 2Al(OH)₃ + 3H₂SO₄ → Al₂(SO₄)₃ + 3H₂O
   Aluminum hydroxide reacts with sulfuric acid to make aluminum sulfate and water. Which reactant is limiting when 0.575 mol aluminum hydroxide are placed in a solution containing 0.500 mol sulfuric acid? How many moles of aluminum sulfate form under these conditions? How many moles of the excess reactant remain after the reaction is complete?
4. Mg(OH)₂ + 2HCl → MgCl₂ + 2H₂O
   Identify the limiting reactant when 5.87 g of magnesium hydroxide reacts with 12.84 g of hydrogen chloride to form magnesium chloride and water. What is the theoretical yield of magnesium chloride in grams?

5. 3Ca + 2FeCl₃ → 3CaCl₂ + 2Fe
   Identify the limiting reactant when 11.2 g of calcium metal reacts with 12.1 g of iron(III) chloride to form calcium chloride and iron metal. What is the theoretical yield of iron metal in grams?
6. C₆H₆ + Br₂ → C₆H₅Br + HBr
   Benzene (C₆H₆) reacts with elemental bromine to make bromobenzene (C₆H₅Br) and hydrobromic acid (HBr). What is the theoretical yield of bromobenzene in this reaction when 30.0 g of benzene reacts with 65.0 g of bromine?
   
   
   
   
   
   
   If the actual yield of bromobenzene was 42.3 g, what was the percentage yield?
7. 8H₂S + 4O₂ → S₈ + 8H₂O
   Hydrogen sulfide is an impurity in natural gas that must be removed. One common removal method is called the Claus process, which relies on a reaction in which the hydrogen sulfide reacts with oxygen to make elemental sulfur (S₈) and water. When conditions are exactly right the Claus process has an efficiency of 98%. That is, the yield of elemental sulfur is 98% of the theoretical yield. If you started with 3.00 g of hydrogen sulfide and 50.0 g of oxygen, how many grams of elemental sulfur would be produced?
8. Zn + 2HCl → H₂ + ZnCl₂
   Zinc and hydrochloric acid react to form hydrogen gas and zinc chloride. How many grams of hydrogen gas would form if you reacted 236 g hydrochloric acid with 257 g zinc? What is the percent yield if 5.79 g of hydrogen gas are produced by the reaction of 236 g hydrochloric acid with 257 g zinc?