NEW
Font size
S
M
L
XL
WorksheetsStoichiometry
Total questions: 35
Worksheet time: 4hrs 6mins
Name
Class
Date
1.
When the limiting reactant in a chemical reaction is completely used, the
a)
reaction slows down
b)
reaction speeds up
c)
excess reactants begin combining
d)
reaction stops
2.
If the percentage yield is equal to 100%, then
a)
the actual yield is greater than the theoretical yield
b)
the actual yield is less than the theoretical yield
c)
the actual yield is equal to the theoretical yield
d)
there was no limiting reactant
3.
To determine the limiting reactant in a chemical reaction, one must know the
a)
amount of product formed
b)
available amount of one of the reactants
c)
available amount of each of each reactant
d)
speed of the reaction
4.
The coefficients in a chemical equation represent the
a)
number of atoms in each compound in a reaction
b)
relative numbers of moles of reactants and products
c)
masses, in grams, of all reactants and products
d)
number of valence electrons involved in the reaction
5.
Which reactant controls the amount of product formed in a chemical reaction?
a)
mole ratio
b)
composition reactant
c)
excess reactant
d)
limiting reactant
6.
For the reaction represented by the equation 2Fe + O2 → 2FeO, how many grams of iron(II) oxide are produced from 8.55 mol of iron in an excess of oxygen?
a)
307 g
b)
8.40 g
c)
447 g
d)
614 g
7.
The actual yield of a chemical reaction is generally
a)
less than the theoretical yield
b)
equal to the theoretical yield
c)
greater than the theoretical yield
d)
greater than the percentage yield
8.
What is the ratio of the actual yield to the theoretical yield, multiplied by 100%?
a)
Avogadro yield
b)
excess yield
c)
percentage yield
d)
mole ratio
9.
For the reaction represented by the equation Pb(NO3)2 + 2 KI → PbI2 + 2 KNO3, how many moles of lead(II) iodide are produced from 239 g of potassium iodide and an excess of lead(II) nitrate?
a)
1.44 mol
b)
0.722 mol
c)
1.44 mol
d)
0.720 mol
10.
In the equation 2KClO3 → 2KCl + 3O2, how many moles of oxygen are produced when 6.7 mol of KClO3 decompose completely?
a)
6.7 mol
b)
1.0 mol
c)
10.1 mol
d)
4.5 mol
11.
What is the maximum possible amount of product obtained in a chemical reaction?
a)
theoretical yield
b)
actual yield
c)
percentage yield
d)
mole ratio
12.
For the reaction represented by the equation SO3 + H2O → H2SO4, how many grams of sulfur trioxide are required to produce 3.94 mol of sulfuric acid in an excess of water?
a)
386 g
b)
20.3 g
c)
0.0492 g
d)
315 g
13.
If, in the reaction A + B → C + D, the quantity of B is insufficient to react with all of A,
a)
A is the limiting reactant
b)
B is the limiting reacant
14.
After calculating the amount of reactant B required to completing react with A, then comparing that amount with the amount of B available, one can determine the
a)
energy released in the reaction
b)
rate of the reaction
c)
pathway of the reaction
d)
limiting reactant
15.
For the reaction represented by the equation 2Na + Cl2 → 2NaCl, how many grams of sodium chloride can be produced from 500. g each of sodium and chlorine?
a)
409 g
b)
824 g
c)
319 g
d)
112 g
16.
If a chemist calculates the maximum amount of product that could be obtained in a chemical reaction, he or she is calculating the
a)
theoretical yield
b)
mole ratio
c)
actual yield
d)
percentage yield
17.
For the reaction represented by the equation 2KClO3 → 2KCl + 3O2, how many moles of potassium chlorate are required to produce 260. g of oxygen?
*The "C" is missing on the test, so "KlO3" should be "KClO3" when you read the question on the test.
*The "C" is missing on the test, so "KlO3" should be "KClO3" when you read the question on the test.
a)
8.13 mol
b)
173 mol
c)
5.42 mol
d)
12.2 mol
18.
For the reaction represented by the equation 2HNO3 + Mg(OH)2 → Mg(NO3)2 + 2H2O, how many grams of magnesium nitrate are produced from 8.64 mol of nictric acid, HNO3, and an excess of Mg(OH)2?
a)
156 g
b)
3
320 g
320 g
c)
445 g
d)
641 g
19.
For the reaction represented by the equation 2Na + 2H2O → 2NaOH + H2, how many grams of hydrogen are produced is 120. g of sodium and 80. g of water are available?
a)
4.5 g
b)
200 g
c)
80. g
d)
45 g
20.
To determine the limiting reactant in a chemical reaction involving known masses of A and B, one could first calculate
a)
the mass of 100 mol A and B
b)
the number of moles of B and the number of of moles of A available
c)
the masses of all products
d)
the bond energies of A and B
21.
For the reaction represented by the equation 3Fe + 4H2O → Fe2O4 + 4H2, how many moles of iron(III) oxide are produced from 437. g of iron in an excess of H2O?
a)
15.6 mol
b)
6.07 mol
c)
2.61 mol
d)
7.82 mol
22.
What is the measured amount of a product obtained from a chemical reaction?
a)
mole ratio
b)
theoretical yield
c)
percentage yield
d)
actual yield
23.
For the reaction represented by the equation 2H2 + O2 → 2H2O, how many moles of water can be produced from 2.1 mol of oxygen?
a)
4.2 mol
b)
1.1 mol
c)
0.95 mol
d)
4 mol
24.
The Haber process for producing ammonia commercially is represented by the equation N2 + 3H2 → 2NH3. To completely convert 7.1 mol hydrogen gas to ammonia gas, how many moles of nitrogen gas are required?
a)
14 mol
b)
3.6 mol
c)
11 mol
d)
4.7 mol
25.
For the reaction represented by the equation Cl2 + 2KBr → Br2 + 2KCl, how many grams of potassium chloride can be produced from 356.g each of chlorine and potassium bromide?
a)
749 g
b)
223 g
c)
479 g
d)
814 g
26.
In the formation of silicon carbide represented by the chemical equation SiO2 + 3C → SiC + 2CO, 8 mol of each reactant are available for the reaction. What substance is the excess reactant?
a)
SiO2
b)
C
c)
SiC
d)
CO
27.
Which of the following mathematical expressions correctly states the relationship among percentage yield, actual yield, and theoretical yield?
a)
theoretical yield = actual yield/percentage yield * 100
b)
percentage yield = actual yield/theoretical yield * 100
c)
Both of these are correct
28.
In the reaction represented by the equation CH4 + 2O2 → CO2 + 2H2O, a mass of 125 g CH4 is reacted with excess oxygen. The expression shown in the picture is used to calculate the
a)
mass of water produced
b)
mass of oxygen reacted
c)
mass of carbon dioxide produced
d)
the expression is wrong
29.
For the reaction represented by the equation Cl2 + 2KBr → Br2 + 2KCl, calculate the percentage yield if 223. g of chlorine react with excess potassium bromide to produce 393. g of bromine.
a)
73.4%
b)
78.2%
c)
82.1%
d)
98.9%
30.
For the reaction represented by the equation CH4 + 2O2 → CO2 + 2H2O, calculate the percentage yield of carbon dioxide if 1000. g of methane react with excess oxygen to produce 2300. of carbon dioxide.
a)
92.76%
b)
78.2%
c)
89.04%
d)
83.88%
31.
A chemical reaction involving substances A and B stops when B is completely used. B is the
a)
excess reactant
b)
primary reactant
c)
limiting reactant
d)
primary product
32.
A chemist interested in the efficiency of a chemical reaction would calculate the
a)
mole ratio
b)
rate of reaction
c)
percentage yield
d)
energy released
33.
In most chemical reactions the amount of product obtained is
a)
less than the theoretical yield
b)
more than the theoretical yield
c)
equal to the theoretical yield
d)
more than the percentage yield
34.
For the reaction represented by the equation CH4 + 2O2 → CO2 + 2H2O, how many moles of carbon dioxide are produced from the combustion of 110. g of methane?
a)
13.7 mol
b)
2.75 mol
c)
6.11 mol
d)
6.85 mol
35.
Ozone, O3, is produced by the reaction represented by the following equation:
NO2 + O2 → NO + O3
What mass of ozone will form the reaction of 1.5 g of NO2 in a car's exhaust and excess oxygen?
NO2 + O2 → NO + O3
What mass of ozone will form the reaction of 1.5 g of NO2 in a car's exhaust and excess oxygen?
a)
1.4 g O3
b)
31 g O3
c)
32 g O3
d)
1.6 g O3
Reset
