Chemistry 534 Chemistry 534 Chemistry 534 Chemistry 534 Chemistry 534 Chemistry 534
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Chemistry 534: Test #8: Stoichiometry
Name: ……………………………………
SAMPLE TEST QUESTIONS
1.
How many moles of potassium chlorate, KClO3 (s) , must be decomposed in
order to produce 36 moles of oxygen gas? The other product is potassium chloride, KCl.
(hint: write the balanced chemical equation.)
2.
A camping lantern uses the reaction of calcium carbide, CaC2 (s) , and water to
produce acetylene gas C2H2 (g) , and calcium hydroxide, Ca(OH)2 (s) . How many
grams of water are required to produce 2.55 moles of acetylene gas?
(hint: write the balanced equation; then solve)
3.
How many litres of oxygen are needed to react completely with 25.0 L of H2S
at STP according to the following reaction:
____ H2S (g) + ___ O2 (g) Æ _____ SO2 (g) + _____ H2O (g)
4.
In a steel cylinder, 42.0 g of N2 are mixed with 9.0 g of H2 . At the end of the
reaction the cylinder contains only NH3 . Calculate the mass of NH3 formed.
N2 (g) + 3 H2 (g) Æ 2 NH3 (g)
5.
Solid lithium hydroxide is used in space vehicles to remove exhaled carbon dioxide from
the living environment to form solid lithium carbonate (Li2CO3) and liquid water. What
mass (in grams) of gaseous carbon dioxide can be absorbed by 1.00 kg of lithium
hydroxide?
6.
When copper is heated with an excess of sulfur, copper (I) sulfide is the product. When
1.50 g of copper was heated with excess sulfur, 1.76 g of copper (I) sulfide was isolated.
What is the theoretical yield? What was the actual percent yield?
7.
How much product is formed when 60.0 g of nitrogen reacts with 10.7 g of
hydrogen to form ammonia gas (NH3) ?
Chemistry 534 Chemistry 534 Chemistry 534 Chemistry 534 Chemistry 534 Chemistry 534
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