Chemistry I Honors
Stoichiometry
Name ___________________________
Period ________
Percent Yield
22. Determine the percent yield for the reaction between 6.92 g of potassium and excess oxygen if
7.36 g of potassium oxide is produced.
23. Determine the percent yield for the reaction between 82.4 g of rubidium and excess oxygen if
39.7 g of rubidium oxide is formed.
24. Determine the percent yield for the reaction between 28.1 g of Sb4O6 and excess carbon if 17.3 g
of antimony is recovered along with an unknown quantity of carbon monoxide.
25. Determine the percent yield for the reaction between 45.9 g of sodium bromide and excess
chlorine if 12.8 g of sodium chloride was recovered.
26. Determine the percent yield for the reaction between 46.1 g of cesium and excess oxygen if only
28.3 g of cesium oxide is produced.
27. Determine the percent yield for the reaction between 15.8 g of ammonia and excess oxygen to
produce 21.8 g of nitrogen monoxide and an unknown amount of water.
28. Determine the percent yield for the reaction between 98.7 g of Sb2S3 and excess oxygen if 72.4 g
of Sb4O6 is recovered along with an unknown amount of sulfur dioxide.
29. Determine the percent yield for the reaction between 46.5 g of zinc sulfide and excess oxygen if
18.4 g of zinc oxide is recovered along with an unknown quantity of sulfur dioxide.
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30. In the commercial production of the element arsenic, arsenic(III) oxide is heated with carbon to
produce carbon dioxide and arsenic. If 8.87 g of arsenic(III) oxide is used in the reaction and
5.33 g of arsenic is produced, what is the percent yield?
Limiting Reactant
31. Given the following unbalanced equation, complete the following statements.
H2 + Cl2 → HCl
a. If 2.0 moles of H2 and 3.0 moles of Cl2 are placed in a reaction chamber,
________________ is the limiting reactant and ______________ mole(s) of HCl is produced.
b. If 0.010 mole of H2 and 0.0050 mole of Cl2 are placed in a reaction chamber,
_______________ is the limiting reactant and _______________ mole(s) of HCl is produced.
c. If 6.0 moles of H2 and 12.0 moles of Cl2 are placed in a reaction chamber,
_______________ is the limiting reactant and _______________ mole(s) of HCl is produced.
32. Given the following unbalanced equation, complete the following statements.
NO + O2 → NO2
a. If 5.0 moles of nitrogen monoxide and 5.0 moles of oxygen are reacted, only one gas is used
up.
_______________ is used up, _______________ is in excess, and
_______________ mole(s) of nitrogen dioxide is formed.
b. If 4.0 moles of nitrogen monoxide and 3.0 moles of oxygen are reacted, only one gas is used
up.
_______________ is used up, _______________ is in excess, and
_______________ mole(s) of nitrogen dioxide is produced.
c. If 5.0 moles of nitrogen monoxide and 2.0 moles of oxygen are reacted, only one gas is used
up.
_______________ is used up,_______________ is in excess, and
_______________ mole(s) of nitrogen dioxide is produced.
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33. Given the following unbalanced equation, complete the following statements.
NH3 + O2 → NO + H2O
a. If 0.068 mole of oxygen is placed in a reaction chamber with 0.050 mole of ammonia,
__________________ is the limiting reactant.
b. If 2.7 moles of oxygen is placed in the chamber with 2.2 moles of ammonia,
__________________ is the limiting reactant.
c. If 8.2 moles of oxygen is placed in the chamber with 5.5 moles of ammonia,
__________________ is the limiting reactant.
34. Given the following unbalanced equation, solve the following problems.(Show work)
Mg + N2 → Mg3N2
a. If 70.0 g of magnesium is reacted with 20.0 g of nitrogen, which is the limiting reactant?
b. If 100.0 g of magnesium is reacted with 42.0 g of nitrogen, the limiting reactant is
_________________.
c. If 1.0 g of magnesium is reacted with 0.50 g of nitrogen, the limiting reactant is
_________________.
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35. Hydrogen sulfide reacts with oxygen to produce water and sulfur dioxide.
a. If 1.00 x 102 g of hydrogen sulfide are burned in the presence of 1.20 x 102 g of oxygen,
calculate the mass of sulfur dioxide produced.
b. If 145 g of sulfur dioxide is recovered, calculate the percent yield.
c. Determine the amount of hydrogen sulfide that remains.
Sequential Reactions
36. Calculate the mass, in kilograms, of pure H2SO4 obtained from 1.000 kg of FeS2 according to the
following sequence of reactions.
4FeS2 + 11O2 → 2Fe2O3 + 8SO2
2SO2 + O2 → 2SO3
SO3 + H2O → H2SO4
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37. Given the following sequence of reactions.
CaCO3 → CaO + CO2
2CO2 + 2C2H5OH → C6H12 O6
How many grams of the sugar can be produced if 70.0 g of an ore containing only 60.0% calcium
carbonate, by weight, are reacted?
38. Small amounts of sulfuric acid are produced industrially by the oxidation of metal sulfides. The
following sequence of unbalanced equations illustrates the manufactor of sulfuric acid from
pyrite, FeS2.
FeS2(s) + O2(g) → Fe2O3(s) + SO2(g)
SO2(g) + O2(g) → SO3(g)
SO3(g) + H2O(l) → H2SO4(l)
What mass of pyrite is required to prepare 1.00 L of liquid H2SO4. The density of liquid H2SO4 is
1.85 g/mL.
Basic Stoichiometry:1. 0.72 mol, 3. 0.19 mol, 5. 0.52 mol, 7. 1.9 mol, 9. 0.090 mol, 11.a. 5, 3, 4, c. 6, e. 24, 13c. 3.675,
e. 1.56 g, g. 14 g, 15.b. 1.5 mol, 17. 0.79 g, 18. 0.11 g, 19. 2.6 g, 20. 0.38 g, 21. 1.5 g
Percent Yield: 22. 88.2%, 23. 44.1%, 24. 73.6%, 25. 49.0%, 26. 57.9%, 27. 78.1%, 28. 85.5%, 29. 47.4%, 30. 79.3%
Limiting Reactant: 31.a. H2, 4.0, b. Cl2, 0.010, c. H2, 12, 33.a. NH3, b. O2, c. NH3, 35.a. 160. g, b. 90.6%, c. 15 g
Sequential Reactions: 36. 1.635 kG, 37. 37.8 g, 38. 1130 g
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