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General, Organic & Biological Chemistry, 5e (Timberlake)
Chapter 7 Chemical Reactions and Quantities
7.1 Multiple-Choice Questions
1) A chemical equation is balanced when
A) the total number of molecules is the same in reactants and products.
B) the total number of ions is the same in reactants and products.
C) the sum of the coefficients of the reactants is equal to the sum of the coefficients of the products.
D) the number of atoms of each element is the same in reactants and products.
E) the charge on each atom is the same in reactants and products.
Answer: D
Objective: 7.1
Global Outcomes: GO2
2) In any balanced chemical equation, the number of each type of atom on both sides of the equation is
A) doubled.
B) the same.
C) decreased by one.
D) increased by one.
E) dependent on the temperature.
Answer: B
Objective: 7.1
Global Outcomes: GO2
3) Which of the following gives the balanced equation for this reaction?
K3PO4 + Ca(NO3)2 → Ca3(PO4)2 + KNO3
A) KPO4 + CaNO3 + KNO3
B) K3PO4 + Ca(NO3)2 → Ca3(PO4)2 + 3KNO3
C) 2K3PO4 + Ca(NO3)2 → Ca3(PO4)2 + 6KNO3
D) 2K3PO4 + 3Ca(NO3)2 → Ca3(PO4)2 + 6KNO3
E) K3PO4 + Ca(NO3)2 → Ca3(PO4)2 + KNO3
Answer: D
Objective: 7.1
Global Outcomes: GO2
1
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4) Which of the following correctly gives the best coefficients for the reaction below?
N2H4 + H2O2 → N2 + H2O
A) 1, 1, 1 ,1
B) 1, 2, 1, 4
C) 2, 4, 2, 8
D) 1, 4, 1, 4
E) 2, 4, 2, 4
Answer: B
Objective: 7.1
Global Outcomes: GO2
5) What coefficient is placed in front of O2 to complete the balancing of the following equation?
C5H8 + ? O2 → 5CO2 + 4H2O
A) 1
B) 3
C) 5
D) 7
E) 9
Answer: D
Objective: 7.1
Global Outcomes: GO2
6) What is the coefficient of hydrogen, H2, when the following equation is balanced?
Al + H2SO4 → Al2(SO4)3 + ? H2
A) 1
B) 2
C) 3
D) 4
E) 5
Answer: C
Objective: 7.1
Global Outcomes: GO2
2
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7) In this reaction, what is the coefficient for calcium oxide?
CaO(s) + CO2(g) → CaCO3(s)
A) 1
B) 2
C) 3
D) 4
E) 5
Answer: A
Objective: 7.1
Global Outcomes: GO2
8) In the following reaction, when the equation is correctly balanced, what is the correct coefficient for
sodium chloride?
Pb(NO3)2(aq) + NaCl(aq) → PbCl2(s) + NaNO3(aq)
A) 1
B) 2
C) 3
D) 4
E) 5
Answer: B
Objective: 7.1
Global Outcomes: GO2
9) In the following reaction, when the equation is correctly balanced, what is the correct coefficient for
H2?
Fe(s) + HCl(aq) → FeCl3(aq) + H2(g)
A) 1
B) 2
C) 3
D) 4
E) 5
Answer: C
Objective: 7.1
Global Outcomes: GO2
3
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10) In the following reaction, when the equation is correctly balanced, what is the correct coefficient for
aluminum chloride?
Al(s) + Cl2(g) → AlCl3(s)
A) 1
B) 2
C) 3
D) 4
E) 5
Answer: B
Objective: 7.1
Global Outcomes: GO2
Pentane (C5H12) reacts with oxygen (O2) to form carbon dioxide (CO2) and water (H2O) according to the
following reaction. Answer the question(s) that follow about this reaction.
C5H12 + ? O2 → ? CO2 + ? H2O
11) What is the coefficient for oxygen in the balanced equation?
A) 2
B) 4
C) 5
D) 6
E) 8
Answer: E
Objective: 7.1
Global Outcomes: GO2
12) What is the coefficient for carbon dioxide in the balanced equation?
A) 2
B) 4
C) 5
D) 6
E) 8
Answer: C
Objective: 7.1
Global Outcomes: GO2
13) What is the coefficient for water in the balanced equation?
A) 2
B) 4
C) 5
D) 6
E) 8
Answer: D
Objective: 7.1
Global Outcomes: GO2
4
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14) In a ________ reaction, two or more elements or compounds form one product.
A) decomposition
B) single replacement
C) dehydration
D) double replacement
E) combination
Answer: E
Objective: 7.2
Global Outcomes: GO2
15) The following reaction takes place when an electric current is passed through water. It is an example
of a ________ reaction.
2H2O → 2H2 + O2
A) combination
B) single replacement
C) dehydration
D) decomposition
E) double replacement
Answer: D
Objective: 7.2
Global Outcomes: GO2
16) What is the classification for this reaction?
SO3 (g) + H2O (l) → H2SO4(l)
A) decomposition
B) combination
C) replacement
D) double replacement
E) oxidation reduction
Answer: B
Objective: 7.2
Global Outcomes: GO2
5
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17) The reaction of carbon with oxygen to produce carbon monoxide is an example of which class of
reaction?
2C(s) + O2(g) → 2CO(g)
A) single replacement
B) double replacement
C) combination
D) catalytic
E) endothermic
Answer: C
Objective: 7.2
Global Outcomes: GO2
18) What is the classification for this unbalanced reaction?
Fe + HCl → FeCl3 + H2
A) dehydration
B) combination
C) decomposition
D) single replacement
E) double replacement
Answer: D
Objective: 7.2
Global Outcomes: GO2
19) The reaction of methane with oxygen to produce carbon dioxide and water is an example of which
class of reaction?
CH4(g) + 2O2(g) → CO2(g) + 2H2O(g)
A) single replacement
B) double replacement
C) combination
D) oxidation
E) endothermic
Answer: D
Objective: 7.2
Global Outcomes: GO2
6
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20) Which of the following is an oxidation-reduction reaction?
A) CaCl2 + Na2SO4 → CaSO4 + 2NaCl
B) KOH + HNO3 → H2O + KNO3
C) N2 + O2 → 2NO
D) AgNO3 + NaCl → AgCl + NaNO3
E) Al2(SO4)3 + 6KOH → 2Al(OH)3 + 3K2SO4
Answer: C
Objective: 7.3
Global Outcomes: GO2
21) What is oxidized and what is reduced in the following reaction?
2Al(s) + 3Br2(g) → 2AlBr3(s)
A) Al is oxidized and Br2 is reduced.
B) AlBr3 is reduced and Br2 is oxidized.
C) Al is reduced and Br2 isoxidized.
D) AlBr3 is reduced and Al is oxidized.
E) AlBr3 is oxidized and Al is reduced.
Answer: A
Objective: 7.3
Global Outcomes: GO2
22) Which of the following describes an oxidation reaction?
A) loss of electrons or loss of oxygen
B) loss of electrons or gain of oxygen
C) loss of electrons or gain of hydrogen
D) gain of electrons or gain of oxygen
E) gain of electrons or loss of H
Answer: B
Objective: 7.3
Global Outcomes: GO2
23) In an oxidation-reduction reaction, the substance oxidized always
A) takes on oxygen atoms.
B) shows a loss of electrons.
C) gives up hydrogen atoms.
D) shows a gain of electrons.
E) becomes a charged species.
Answer: B
Objective: 7.3
Global Outcomes: GO2
7
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24) In this reaction, what is the substance oxidized?
Zn(s) + 2 HCl(aq) → ZnCl2(aq) + H2(g)
A) chlorine
B) zinc chloride
C) hydrogen
D) zinc
E) oxygen
Answer: D
Objective: 7.3
Global Outcomes: GO2
25) In an oxidation-reduction reaction, the substance reduced always
A) takes on oxygen atoms.
B) shows a loss of electrons.
C) gives up hydrogen atoms.
D) shows a gain of electrons.
E) becomes a charged species.
Answer: D
Objective: 7.3
Global Outcomes: GO2
26) How many moles of iron are present in 3.15 × 1024 atoms of iron?
A) 5.23 moles
B) 1.90 moles
C) 292 moles
D) 0.523 moles
E) 1.90 × 1048 moles
Answer: A
Objective: 7.4
Global Outcomes: GO4
27) How many atoms of neon are present in 1.30 moles of neon?
A) 3.15 × 1023 atoms
B) 4.63 × 1023 atoms
C) 7.83 × 1023 atoms
D) 6.02 × 1023 atoms
E) 7.83 × 1024 atoms
Answer: C
Objective: 7.4
Global Outcomes: GO4
8
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28) One mole of particles of any substance contains how many particles?
A) 106
B) 3 × 10-10
C) 3 × 1010
D) 6.02 × 1023
E) 6.02 × 10-23
Answer: D
Objective: 7.4
Global Outcomes: GO4
29) Avogadro's number is the number of
A) particles in 1 mole of a substance.
B) amu in 1 mole of a substance.
C) grams in 1 mole of a substance.
D) moles in 6.02 × 1023 grams of an element.
E) moles in 6.02 × 1023 amu of an element.
Answer: A
Objective: 7.4
Global Outcomes: GO4
30) How many molecules of water, H2O, are present in 75.0 g of H2O?
A) 75.0 molecules
B) 4.17 molecules
C) 7.53 × 1024 molecules
D) 2.51 × 1024 molecules
E) 5.02 × 1024 molecules
Answer: D
Objective: 7.5
Global Outcomes: GO4
31) How many hydrogen atoms are present in 75.0 g of H2O?
A) 75.0 atoms
B) 4.17 atoms
C) 7.53 × 1024 atoms
D) 2.51 × 1024 atoms
E) 5.02 × 1024 atoms
Answer: E
Objective: 7.5
Global Outcomes: GO4
9
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32) The molar mass of potassium is
A) 19 g.
B) 31.0 g.
C) 6.02 × 1023 grams.
D) 39.1 g.
E) 15g.
Answer: D
Objective: 7.5
Global Outcomes: GO4
33) One mole of helium gas has a mass of
A) 1.00 g.
B) 2.00 g.
C) 3.00 g.
D) 4.00 g.
E) 8.00 g.
Answer: D
Objective: 7.5
Global Outcomes: GO4
34) How many moles of water, H2O, are present in 75.0 g of H2O?
A) 4.41 moles
B) 4.16 moles
C) 75.0 moles
D) 7.50 moles
E) 1.35 × 103 moles
Answer: B
Objective: 7.5
Global Outcomes: GO4
35) 0.100 mole of lithium has a mass of
A) 3.00 g.
B) 0.300 g.
C) 6.94 g.
D) 0.694 g.
E) 0.700 g.
Answer: D
Objective: 7.5
Global Outcomes: GO4
36) Calculate the molar mass of potassium chloride, KCl.
A) 74.6 g
B) 54.5 g
C) 6.74 g
D) 67.4 g
E) 19.0 g
Answer: A
Objective: 7.5
Global Outcomes: GO4
10
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37) What is the molar mass of copper(II) sulfate, CuSO4?
A) 16.0 g
B) 63.6 g
C) 111.6 g
D) 159.6 g
E) 319.2 g
Answer: D
Objective: 7.5
Global Outcomes: GO4
38) Calculate the molar mass of magnesium chloride, MgCl 2.
A) 24.3 g
B) 95.2 g
C) 125.9 g
D) 59.8 g
E) 70.0 g
Answer: B
Objective: 7.5
Global Outcomes: GO4
39) What is the molar mass of sodium phosphate, Na3PO4?
A) 119 g
B) 308 g
C) 164 g
D) 226 g
E) 354 g
Answer: C
Objective: 7.5
Global Outcomes: GO4
40) How many moles of carbon atoms are there in 0.500 mole of C2H6?
A) 0.500 moles
B) 1.00 moles
C) 3.00 moles
D) 6.02 × 1023 moles
E) 4.00 moles
Answer: B
Objective: 7.5
Global Outcomes: GO4
11
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41) What is the molar mass of sucrose (C12H22O11)?
A) 29.0 g
B) 50.2 g
C) 210 g
D) 342 g
E) 182 g
Answer: D
Objective: 7.5
Global Outcomes: GO4
42) One mole of neon atoms has a mass of
A) 6.02 × 1023 grams.
B) 14.0 g.
C) 10.0 g.
D) 20.2 g.
E) 30.2 g.
Answer: D
Objective: 7.5
Global Outcomes: GO4
43) The molar mass of C3H8O2 is
A) 76.0 g.
B) 60.0 g.
C) 29.0 g.
D) 69.0 g.
E) 52.0 g.
Answer: A
Objective: 7.5
Global Outcomes: GO4
44) The molar mass of calcium hydroxide, Ca(OH) 2, is
A) 58.1 g.
B) 57.1 g.
C) 74.1 g.
D) 114.2 g.
E) 38.0 g.
Answer: C
Objective: 7.5
Global Outcomes: GO4
12
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45) What is the molar mass of Mg3(PO4)2, a substance formerly used in medicine as an antacid?
A) 71.3 g
B) 118 g
C) 150. g
D) 214 g
E) 263 g
Answer: E
Objective: 7.5
Global Outcomes: GO4
46) 4.00 moles of sodium have a mass of
A) 4.60 g.
B) 11.0 g.
C) 23.0 g.
D) 44.0 g.
E) 92.0 g.
Answer: E
Objective: 7.5
Global Outcomes: GO4
47) How many moles of K2SO4 are in 15.0 g of K2SO4?
A) 0.172 moles
B) 2.61 × 103 moles
C) 0.111 moles
D) 0.0861 moles
E) 0.119 moles
Answer: D
Objective: 7.5
Global Outcomes: GO4
48) 3.00 moles of NO2 have a mass of
A) 138 g.
B) 46.0 g.
C) 30.0 g.
D) 90.0 g.
E) 45.0 g.
Answer: A
Objective: 7.5
Global Outcomes: GO4
13
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49) 1.25 moles of PbO2 have a mass of
A) 191 g.
B) 279 g.
C) 178 g.
D) 239 g.
E) 299 g.
Answer: E
Objective: 7.5
Global Outcomes: GO4
50) How many grams of Fe2O3 are there in 0.500 mole of Fe2O3?
A) 79.9 g
B) 35.9 g
C) 63.8 g
D) 51.9 g
E) 160. g
Answer: A
Objective: 7.5
Global Outcomes: GO4
51) How many grams of glucose (C6H12O6) are in 3.55 moles of glucose?
A) 180. g
B) 639 g
C) 103 g
D) 426 g
E) 50.7 g
Answer: B
Objective: 7.5
Global Outcomes: GO4
14
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52) Given the following equation, what is the correct form of the conversion factor needed to convert the
number of moles of O2 to the number of moles of Fe2O3 produced?
4Fe(s) + 3O2 (g) → 2Fe2O3(s)
A)
B)
C)
D)
E)
Answer: E
Objective: 7.6
Global Outcomes: GO4
For the question(s) that follow, consider the following equation.
2Mg + O → 2MgO
2
53) The number of moles of oxygen gas needed to react with 4.0 moles of Mg is
A) 1.0 mole.
B) 2.0 moles.
C) 3.0 moles.
D) 4.0 moles.
E) 6.0 moles.
Answer: B
Objective: 7.6
Global Outcomes: GO4
54) The number of moles of MgO produced when 0.20 mole of O 2 reacts completely is
A) 0.10 mole.
B) 0.20 mole.
C) 0.40 mole.
D) 0.60 mole.
E) 0.80 mole.
Answer: C
Objective: 7.6
Global Outcomes: GO4
15
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55) How many moles of magnesium are needed to react with 0.50 mole of O 2?
A) 0.50 mole
B) 1.0 moles
C) 2.0 moles
D) 3.0 moles
E) 4.0 moles
Answer: B
Objective: 7.6
Global Outcomes: GO4
56) When 4 moles of aluminum are allowed to react with an excess of chlorine gas, Cl 2, how many moles
of aluminum chloride are produced?
A) 1 mole
B) 2 moles
C) 3 moles
D) 4 moles
E) 5 moles
Answer: D
Objective: 7.6
Global Outcomes: GO4
57) In the reaction of nitrogen gas, N2, with hydrogen gas, H2, to form ammonia gas, NH3 , how many
moles of hydrogen are needed to react with two moles of nitrogen?
A) 2 moles
B) 4 moles
C) 6 moles
D) 8 moles
E) 10 moles
Answer: C
Objective: 7.6
Global Outcomes: GO4
16
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For the question(s) that follow, consider the following balanced equation.
Mg3N2(s) + 6H2O(l) → 3Mg (OH)2(s) + 2NH3(g)
58) What is the correct form of the conversion factor needed to convert the number of moles of H 2O to the
number of moles of NH3 produced?
A)
B)
C)
D)
E)
Answer: A
Objective: 7.6
Global Outcomes: GO4
59) When 2 moles of Mg3N2 are allowed to react, how many moles of H2O also react?
A) 1 mole
B) 4 moles
C) 6 moles
D) 8 moles
E) 12 moles
Answer: E
Objective: 7.6
Global Outcomes: GO4
For the question(s) that follow, consider the following equation.
2Mg + O2 → 2MgO
60) How many grams of MgO are produced when 40.0 grams of O 2 react completely with Mg?
A) 30.4 g
B) 50.4 g
C) 60.8 g
D) 101 g
E) 201 g
Answer: D
Objective: 7.7
Global Outcomes: GO4
17
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For the question(s) that follow, consider the following balanced equation.
Mg3N2(s) + 6H2O(l) → 3Mg (OH)2(s) + 2NH3(g)
61) How many grams of H2O are needed to produce 150 g of Mg(OH)2?
A) 46 g
B) 18 g
C) 130 g
D) 93 g
E) 23 g
Answer: D
Objective: 7.7
Global Outcomes: GO4
62) When 36.0 g of H2O react, how many grams of NH3 are produced?
A) 34.0 g
B) 10.0 g
C) 5.67 g
D) 11.3 g
E) 102 g
Answer: D
Objective: 7.7
Global Outcomes: GO4
63) How many grams of hydrogen are needed to produce 1.80 g of water according to this equation?
2H2 + O2 → 2H2O
A) 0.100 g
B) 0.180 g
C) 0.200 g
D) 2.00 g
E) 4.00 g
Answer: C
Objective: 7.7
Global Outcomes: GO4
18
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64) In the reaction of silver nitrate with sodium chloride, how many grams of silver chloride will be
produced from 100. g of silver nitrate when it is mixed with an excess of sodium chloride? The equation
for the reaction is below.
AgNO3(aq) + NaCl(aq) → AgCl(s) + NaNO3(aq)
A) 107.9 g
B) 169.9 g
C) 84.4 g
D) 0.589 g
E) 58.9 g
Answer: C
Objective: 7.7
Global Outcomes: GO4
65) Find the mass of AlCl3 that is produced when 25.0 grams of Al 2O3 react with excess HCl according to
the following equation.
Al2O3(s) + 6HCl(aq) → 2AlCl3(aq) + 3H2O(l)
A) 155 g
B) 72.9 g
C) 65.4 g
D) 32.6 g
E) 16.3 g
Answer: C
Objective: 7.7
Global Outcomes: GO4
66) How many grams of NO are required to produce 145 g of N 2 in the following reaction?
4NH3(g) + 6NO(g) → 5N2(g) + 6H2O(l)
A) 186 g
B) 155 g
C) 125 g
D) 129 g
E) 145 g
Answer: A
Objective: 7.7
Global Outcomes: GO4
19
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67) How many grams of N2 are produced from 100. g of NH3 in the following reaction?
4NH3(g) + 6NO(g) → 5N2(g) + 6H2O(l)
A) 165 g
B) 132 g
C) 125 g
D) 206 g
E) 7.35 g
Answer: D
Objective: 7.7
Global Outcomes: GO4
68) How many grams of CO2 are produced from 125 g of O2 and excess CH4?
CH4 + 2O2 → CO2 + 2H2O
A) 125 g of CO2
B) 62.5 g of CO2
C) 172 g of CO2
D) 85.9 g of CO2
E) 250. g of CO2
Answer: D
Objective: 7.7
Global Outcomes: GO4
69) When 3.05 moles of CH4 are mixed with 5.03 moles of O2 the limiting reactant is
CH4 + 2O2 → CO2 + 2H2O
A) CH4.
B) O2.
C) CO2.
D) H2O.
Answer: B
Objective: 7.8
Global Outcomes: GO4
20
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70) When 85.0 g of CH4 are mixed with 160. g of O2 the limiting reactant is
CH4 + 2O2 → CO2 + 2H2O
A) CH4.
B) O2.
C) CO2.
D) H2O.
Answer: B
Objective: 7.8
Global Outcomes: GO4
71) When 10.0 g of NH3 reacts, the actual yield of N2 is 8.50 g. What is the percent yield?
4NH3(g) + 6NO(g) → 5N2(g) + 6H2O(l)
A) 85.0%
B) 51.5%
C) 20.6%
D) 41.3%
E) 8.5%
Answer: D
Objective: 7.8
Global Outcomes: GO7
72) When 85.0 g of CH4 are mixed with 160. g of O2 what is the maximum amount of CO2 that can be
produced?
CH4 + 2O2 → CO2 + 2H2O
A) 2.50 moles
B) 5.00 moles
C) 5.31 moles
D) 7.81 moles
Answer: A
Objective: 7.8
Global Outcomes: GO4
21
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73) When 60.0 g of CH4 reacts with excess O2, the actual yield of CO2 is 112 g. What is the percent yield?
CH4 + 2O2 → CO2 + 2H2O
A) 53.6 %
B) 187 %
C) 67.9 %
D) 46.4 %
Answer: C
Objective: 7.8
Global Outcomes: GO4
74) Find the mass of AlCl3 that is produced when 10.0 grams of Al 2O3 react with 10.0 g of HCl according
to the following equation.
Al2O3(s) + 6HCl(aq) → 2AlCl3(aq) + 3H2O(aq)
A) 16.2 g
B) 20.0 g
C) 12.2 g
D) 10.0 g
E) 6.10 g
Answer: C
Objective: 7.8
Global Outcomes: GO4
75) What type of reaction is: CH4 + 2O2 → CO2 + 2H2O + 218 kcal?
A) an endothermic reaction
B) an exothermic reaction
C) a single replacement reaction
D) a combination reaction
E) a decomposition reaction
Answer: B
Objective: 7.9
Global Outcomes: GO2
76) How many kcal are produced when 32.0 g of CH4 react?
CH4 + 2O2 → CO2 + 2H2O + 218 kcal
A) 218 kcal
B) 109 kcal
C) 436 kcal
D) 6.81 kcal
E) 698 kcal
Answer: C
Objective: 7.9
Global Outcomes: GO4
22
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77) For the reaction: 2H2O(l) + 137 kcal → 2H2 (g) + O2 (g), how many kcal are needed to form 2.00 moles
O2 (g)?
A) 68.5 kcal
B) 137 kcal
C) 274 kcal
D) 190. kcal
E) 548 kcal
Answer: C
Objective: 7.9
Global Outcomes: GO4
78) For the reaction: 2H2O(l) + 137 kcal → 2H2 (g) + O2 (g), how many kcal are needed to react 50.0 g
H2O(l)?
A) 380. kcal
B) 137 kcal
C) 274 kcal
D) 190. kcal
E) 760. kcal
Answer: D
Objective: 7.9
Global Outcomes: GO4
79) If the reaction shown below is exothermic, the energy level of the reactants is
H2 + O2 → 2H2O
A) lower than that of the products.
B) higher than that of the products.
C) the same as that of the products.
D) possibly lower, possibly higher than that of the products.
E) higher than the activation energy of the reaction.
Answer: B
Objective: 7.9
Global Outcomes: GO2
80) In an endothermic reaction
A) heat flows out of the system.
B) energy is absorbed by the system.
C) the temperature of the system increases.
D) the products have less energy that the reactants.
E) the products have the same energy that the reactants.
Answer: B
Objective: 7.9
Global Outcomes: GO2
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81) Any reaction that absorbs 150 kcal of energy can be classified as
A) endothermic.
B) exothermic.
C) activated.
D) reduction.
E) oxidation.
Answer: A
Objective: 7.9
Global Outcomes: GO2
82) The ________ is the energy difference between reactants and products in a chemical reaction.
A) transition energy
B) activation energy
C) product energy
D) overall energy
E) heat of reaction
Answer: E
Objective: 7.9
Global Outcomes: GO2
83) The ________ is the minimum energy needed for a chemical reaction to begin.
A) reaction energy
B) activation energy
C) energy of reactants
D) energy of products
E) heat of reaction
Answer: B
Objective: 7.9
Global Outcomes: GO2
84) A reaction that releases energy as it occurs is classified as a(n)
A) endothermic reaction.
B) exothermic reaction.
C) oxidation-reduction reaction.
D) catalyzed reaction.
E) decomposition reaction.
Answer: B
Objective: 7.9
Global Outcomes: GO2
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7.2 Bimodal Questions
1) In this reaction, what is the correct coefficient for hydrogen gas?
? H2 + ? O2 → ? H2O
A) 1
B) 2
C) 3
D) 4
E) 5
Answer: B
Objective: 7.1
Global Outcomes: GO4
Barium chloride and sodium sulfate react according to the following equation.
BaCl2 + Na2SO4 → BaSO4 + 2NaCl
Answer the question(s) that follow about this reaction.
2) How many moles of barium sulfate are produced from 0.100 mole of barium chloride?
A) 0.0100 mole
B) 0.100 mole
C) 0.200 mole
D) 1.00 mole
E) 2.00 moles
Answer: B
Objective: 7.6
Global Outcomes: GO4
3) How many grams of barium sulfate can be produced from 20.8 g of barium chloride?
A) 1.37 g
B) 2.33 g
C) 23.3 g
D) 137 g
E) 233 g
Answer: C
Objective: 7.7
Global Outcomes: GO4
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4) How many grams of barium chloride are needed to make 100. grams of barium sulfate?
A) 44.9 g
B) 89.2 g
C) 208.3 g
D) 233.3 g
E) 46.6 g
Answer: B
Objective: 7.7
Global Outcomes: GO4
Answer the question(s) that follow about the following reaction.
2H2O2 → 2H2O + O2
5) How many moles of oxygen gas can 0.88 mole of hydrogen peroxide (H 2O2) produce, if decomposition
is complete?
A) 0.50 mole
B) 0.88 mole
C) 1.8 moles
D) 2.0 moles
E) 0.44 mole
Answer: E
Objective: 7.6
Global Outcomes: GO4
6) How many grams of water will 100. grams of hydrogen peroxide (H 2O2) produce?
A) 3600 g
B) 360. g
C) 5.88 g
D) 52.9 g
E) 106 g
Answer: D
Objective: 7.7
Global Outcomes: GO4
7) How many grams of hydrogen peroxide (H2O2) are needed to produce 25.0 g of oxygen?
A) 106 g
B) 26.6 g
C) 5.88 g
D) 25.0 g
E) 53.1 g
Answer: E
Objective: 7.7
Global Outcomes: GO4
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8) How many moles of hydrogen peroxide (H2O2) are needed to produce 5.0 moles of water?
A) 1.0 mole
B) 2.0 moles
C) 4.0 moles
D) 5.0 moles
E) 8.0 moles
Answer: D
Objective: 7.6
Global Outcomes: GO4
7.3 Short Answer Questions
1) What type of reaction is the following?
2KClO3 → 2KCl + 3O2
Answer: decomposition reaction
Objective: 7.2
Global Outcomes: GO2
2) What type of reaction is the following?
Zn + 2HCl → ZnCl2 + H2
Answer: single replacement reaction
Objective: 7.2
Global Outcomes: GO2
3) What type of reaction is the following?
2KClO3 → 2KCl + 3O2
Answer: decomposition reaction
Objective: 7.2
Global Outcomes: GO2
4) What type of reaction is the following?
Zn + 2HCl → ZnCl2 + H2
Answer: single replacement reaction
Objective: 7.2
Global Outcomes: GO2
5) The number of particles in 1 mole of hydrogen gas is ________.
Answer: 6.02 × 1023
Objective: 7.4
Global Outcomes: GO4
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6) The molar mass of copper(II) nitrate, Cu(NO3)2 is ________.
Answer: 187.6 g
Objective: 7.5
Global Outcomes: GO4
7) What is the mass of 1 mole of argon gas?
Answer: 40.0 g
Objective: 7.5
Global Outcomes: GO4
8) What is the mass of 1 mole of helium gas?
Answer: 4.00 g
Objective: 7.5
Global Outcomes: GO4
9) Acetylene gas, C2H2, reacts with oxygen according to the following equation. If 1.00 mole of acetylene
reacts completely with sufficient oxygen, how many moles of carbon dioxide are produced?
2C2H2 + 5O2 → 4CO2 + 2H2O
Answer: 2.00 moles of CO2
Objective: 7.6
Global Outcomes: GO4
7.4 True/False Questions
1) The following reaction is balanced.
KClO3 → KCl + O2
Answer: FALSE
Objective: 7.1
Global Outcomes: GO2
2) The following is a decomposition reaction.
2KClO3 → 2KCl + 3O2
Answer: TRUE
Objective: 7.2
Global Outcomes: GO2
3) Loss of electrons is an oxidation.
Answer: TRUE
Objective: 7.3
Global Outcomes: GO2
4) Avogadro's number is the number of grams in a mole.
Answer: FALSE
Objective: 7.4
Global Outcomes: GO4
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5) The molar mass of silver is 47 g.
Answer: FALSE
Objective: 7.5
Global Outcomes: GO4
6) The molar mass of magnesium is 24.3 g.
Answer: TRUE
Objective: 7.5
Global Outcomes: GO4
7) The mass of one mole of water is 18.0 g.
Answer: TRUE
Objective: 7.5
Global Outcomes: GO4
8) The molar mass of chlorine gas is 35.5 g.
Answer: FALSE
Objective: 7.5
Global Outcomes: GO4
9) The molar mass of copper(II) chloride is 134.5 g.
Answer: TRUE
Objective: 7.5
Global Outcomes: GO4
10) In the reaction of hydrogen gas with oxygen gas to produce water, 1 mole of oxygen gas can produce
2 moles of water, given sufficient hydrogen available.
Answer: TRUE
Objective: 7.6
Global Outcomes: GO4
11) In the reaction of hydrogen gas with oxygen gas to produce water, 16.0 g of oxygen gas can produce
9.00 g of water, given sufficient hydrogen available.
2H2 + O2 → 2H2O
Answer: FALSE
Objective: 7.7
Global Outcomes: GO4
12) The % yield is the ratio of the theoretical yield to the actual yield multiplied by 100.
Answer: FALSE
Objective: 7.9
Global Outcomes: GO2
13) In an exothermic reaction, heat is a product.
Answer: TRUE
Objective: 7.9
Global Outcomes: GO1
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7.5 Matching Questions
Identify the energy associated with each of the labeled parts of the following diagram.
A) energy of reactants
B) heat of reaction
C) activation energy
D) energy of products
1) Region A
Objective: 7.9
Global Outcomes: GO3
2) Region B
Objective: 7.9
Global Outcomes: GO3
3) Region C
Objective: 7.9
Global Outcomes: GO3
4) Region D
Objective: 7.9
Global Outcomes: GO3
Answers: 1) A 2) C 3) B 4) D
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Identify the letter of the diagram corresponding to the given type of reaction.
A
B
A) Diagram A
B) Diagram B
5) endothermic reaction
Objective: 7.9
Global Outcomes: GO3
6) exothermic reaction
Objective: 7.9
Global Outcomes: GO3
Answers: 5) B 6) A
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