Chemistry: A Molecular Approach, 3e (Tro)
Chapter 13 Chemical Kinetics
Multiple Choice Questions
1) Identify the methods used to monitor a reaction as it occurs in the reaction flask.
A) polarimeter
B) spectrometer
C) pressure measurement
D) none of the above
E) all of the above
Answer: E
Diff: 1
Page Ref: 13.2
2) Given the following balanced equation, determine the rate of reaction with respect to [NOCl].
2 NO(g) + Cl2(g) → 2 NOCl(g)
A) Rate = B) Rate = +
C) Rate = D) Rate = E) It is not possible to determine without more information.
Answer: B
Diff: 2
Page Ref: 13.2
1
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3) Given the following balanced equation, determine the rate of reaction with respect to [H2].
N 2(g) + 3 H2(g) → 2 NH3(g)
A) Rate = +
B) Rate = C) Rate = +
D) Rate = E) It is not possible to determine without more information.
Answer: D
Diff: 2
Page Ref: 13.2
4) Given the following balanced equation, determine the rate of reaction with respect to [NH3].
N 2(g) + 3 H2(g) → 2 NH3(g)
A) Rate = +
B) Rate = C) Rate = +
D) Rate = E) It is not possible to determine without more information.
Answer: C
Diff: 2
Page Ref: 13.2
2
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5) Given the following balanced equation, determine the rate of reaction with respect to [N 2].
N 2(g) + 3 H2(g) → 2 NH3(g)
A) Rate = +
B) Rate = C) Rate = +
D) Rate = E) It is not possible to determine without more information.
Answer: B
Diff: 2
Page Ref: 13.2
6) Write a balanced reaction for which the following rate relationships are true.
Rate = -
=
=
A) 2 N 2O5 → 4 NO 2 + O2
B) 4 NO 2 + O2 → 2 N2O5
C) 2 N 2O5 → NO 2 + 4 O2
D)
NO 2 + O2 →
E)
N 2O 5 →
N 2O5
NO2 + O2
Answer: A
Diff: 2
Page Ref: 13.2
3
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7) Write a balanced reaction for which the following rate relationships are true.
Rate =
A)
=
N2 + O2 →
=-
N 2O
B) 2 N 2O → 2 N 2 + O2
C) N 2O → N 2 + 2 O 2
D)
N 2O →
N2 + O2
E) 2 N 2 + O2 → 2 N2O
Answer: B
Diff: 2
Page Ref: 13.2
8) Give the characteristic of a first order reaction having only one reactant.
A) The rate of the reaction is not proportional to the concentration of the reactant.
B) The rate of the reaction is proportional to the square of the concentration of the reactant.
C) The rate of the reaction is proportional to the square root of the concentration of the reactant.
D) The rate of the reaction is proportional to the natural logarithm of the concentration of the reactant.
E) The rate of the reaction is directly proportional to the concentration of the reactant.
Answer: E
Diff: 1
Page Ref: 13.3
9) Give the characteristic of a zero order reaction having only one reactant.
A) The rate of the reaction is not proportional to the concentration of the reactant.
B) The rate of the reaction is proportional to the square of the concentration of the reactant.
C) The rate of the reaction is proportional to the square root of the concentration of the reactant.
D) The rate of the reaction is proportional to the natural logarithm of the concentration of the reactant.
E) The rate of the reaction is directly proportional to the concentration of the reactant.
Answer: A
Diff: 1
Page Ref: 13.3
10) Give the characteristic of a second order reaction having only one reactant.
A) The rate of the reaction is not proportional to the concentration of the reactant.
B) The rate of the reaction is proportional to the square of the concentration of the reactant.
C) The rate of the reaction is proportional to the square root of the concentration of the reactant.
D) The rate of the reaction is proportional to the natural logarithm of the concentration of the reactant.
E) The rate of the reaction is directly proportional to the concentration of the reactant.
Answer: B
Diff: 1
Page Ref: 13.3
4
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11) What is the overall order of the following reaction, given the rate law?
NO(g) + O 3(g) → NO 2(g) + O 2(g) Rate = k[NO][O 3]
A) 1st order
B) 2nd order
C) 3rd order
D) 1
order
E) 0th order
Answer: B
Diff: 2
Page Ref: 13.3
12) What are the units of k in the following rate law?
Rate = k[X][Y]2
A)
B)
C) M2 s
D)
E)
Answer: B
Diff: 2
Page Ref: 13.3
5
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13) What are the units of k in the following rate law?
Rate = k[X]2[Y]2
A)
B)
C) M2 s
D)
E)
Answer: E
Diff: 2
Page Ref: 13.3
14) What are the units of k in the following rate law?
Rate = k[X][Y]
A)
B) Ms
C)
D)
E)
Answer: C
Diff: 2
Page Ref: 13.3
6
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15) What are the units of k in the following rate law?
Rate = k[X]
A)
B) Ms
C)
D)
E)
Answer: D
Diff: 2
Page Ref: 13.3
16) What are the units of k in the following rate law?
Rate = k[X]0[Y]0
A)
B) Ms
C) M-1s-1
D)
E)
Answer: D
Diff: 2
Page Ref: 13.3
17) What are the units of k in the following rate law?
Rate = k[X][Y]1/2
A) M/s
B) M-1s-1
C) M1/2s-1
D) M-1/2s-1
E) M-1s-1/2
Answer: D
Diff: 2
Page Ref: 13.3
7
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18) What are the units of k in the following rate law?
Rate = k[X]2
A) Ms-1
B) Ms
C) M-1s-1
D) M-2s-1
E) M2s-1
Answer: C
Diff: 2
Page Ref: 13.3
19) Determine the rate law and the value of k for the following reaction using the data provided.
CO(g) + Cl2(g) → COCl2(g)
[CO]i (M)
0.25
0.25
0.50
[Cl2]i (M)
0.40
0.80
0.80
Initial Rate (M-1s-1)
0.696
1.97
3.94
A) Rate = 11 M-3/2s-1 [CO][Cl2]3/2
B) Rate = 36 M-1.8s-1 [CO][Cl2]2.8
C) Rate = 17 M-2s-1 [CO][Cl2]2
D) Rate = 4.4 M-1/2s-1 [CO][Cl2]1/2
E) Rate = 18 M-3/2s-1 [CO]2[Cl2]1/2
Answer: A
Diff: 3
Page Ref: 13.3
20) Determine the rate law and the value of k for the following reaction using the data provided.
S2O 82⁻(aq) + 3 I⁻(aq) → 2 SO 42⁻(g) + I3⁻(aq)
[S2O82⁻]i (M) [I⁻]i (M)
0.30
0.42
0.44
0.42
0.44
0.21
A) Rate = 120 M-2s-1 [S2O82⁻]2[I⁻]
B) Rate = 36 M-1s-1 [S2O 82⁻][I⁻]
C) Rate = 86 M-2s-1 [S2O 82⁻][I⁻]2
D) Rate = 195 M-3s-1 [S2O82⁻]2[I⁻]2
E) Rate = 23 M-1/2s-1 [S2O82⁻][I⁻]1/2
Answer: B
Diff: 3
Page Ref: 13.3
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Initial Rate (M-1s-1)
4.54
6.65
3.33
21) Determine the rate law and the value of k for the following reaction using the data provided.
NO2(g) + O 3(g) → NO 3(g) + O 2(g)
[NO 2]i (M)
0.10
0.10
0.25
[O3]i (M)
0.33
0.66
0.66
Initial Rate (M-1s-1)
1.42
2.84
7.10
A) Rate = 1360 M-2.5s-1[NO 2]2.5[O3]
B) Rate = 227 M-2.5s-1[NO 2][O3]2.5
C) Rate = 43 M-1s-1[NO 2][O3]
D) Rate = 430 M-2s-1[NO 2]2[O3]
E) Rate = 130 M-2s-1[NO 2][O3]2
Answer: C
Diff: 3
Page Ref: 13.3
22) Determine the rate law and the value of k for the following reaction using the data provided.
2 NO(g) + O 2(g) → 2 NO 2(g) [NO]i (M)
0.030
0.030
0.060
[O2]i (M)
0.0055
0.0110
0.0055
Initial Rate (M-1s-1)
8.55 x 10-3
1.71 x 10-2
3.42 x 10-2
A) Rate = 57 M-1s-1[NO][O 2]
B) Rate = 3.8 M-1/2s-1[NO][O 2]1/2
C) Rate = 3.1 × 105 M-3s-1[NO]2[O2]2
D) Rate = 1.7 × 103 M-2s-1[NO]2[O2]
E) Rate = 9.4 × 103 M-2s-1[NO][O 2]2
Answer: D
Diff: 3
Page Ref: 13.3
23) Carbon-14 has a half-life of 5720 years and this is a first order reaction. If a piece of wood has
converted 75% of the carbon-14, then how old is it?
A) 11440 years
B) 2375 years
C) 4750 years
D) 4290 years
E) 1430 years
Answer: A
Diff: 3
Page Ref: 13.4
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24) Carbon-14 has a half-life of 5720 years and this is a first order reaction. If a piece of wood has
converted 25% of the carbon-14, then how old is it?
A) 11440 years
B) 2375 years
C) 4750 years
D) 4290 years
E) 1430 years
Answer: B
Diff: 3
Page Ref: 13.4
25) Which of the following represents the integrated rate law for a first-order reaction?
A)
B)
= - kt
-
= kt
C) [A]t - [A]o = - kt
D) k = Ae(-Ea/RT)
E)
=
( ) + lnA
Answer: A
Diff: 1
Page Ref: 13.4
26) Which of the following represents the integrated rate law for a second-order reaction?
A)
B)
= - kt
-
= kt
C) [A]t - [A]o = - kt
D) k = Ae(-Ea/RT)
E)
=
( ) + lnA
Answer: B
Diff: 1
Page Ref: 13.4
10
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27) Which of the following represents the integrated rate law for a zeroth-order reaction?
A)
B)
= - kt
-
= kt
C) [A]t - [A]o = - kt
D) k = Ae(-Ea/RT)
E)
=
( ) + lnA
Answer: C
Diff: 1
Page Ref: 13.4
28) What data should be plotted to show that experimental concentration data fits a first-order reaction?
A) 1/[reactant] vs. time
B) [reactant] vs. time
C) ln[reactant] vs. time
D) ln(k) vs. 1/T
E) ln(k) vs. Ea
Answer: C
Diff: 1
Page Ref: 13.4
29) What data should be plotted to show that experimental concentration data fits a second-order
reaction?
A) ln[reactant] vs. time
B) [reactant] vs. time
C) ln(k) vs. 1/T
D) 1/[reactant] vs. time
E) ln(k) vs. Ea
Answer: D
Diff: 1
Page Ref: 13.4
30) What data should be plotted to show that experimental concentration data fits a zeroth-order
reaction?
A) ln[reactant] vs. time
B) 1/[reactant] vs. time
C) ln(k) vs. 1/T
D) ln(k) vs. Ea
E) [reactant] vs. time
Answer: E
Diff: 1
Page Ref: 13.4
11
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31) Which of the following statements is FALSE?
A) The average rate of a reaction decreases during a reaction.
B) It is not possible to determine the rate of a reaction from its balanced equation.
C) The rate of zero order reactions are not dependent on concentration.
D) The half life of a first order reaction is dependent on the initial concentration of reactant.
E) None of the statements are FALSE.
Answer: D
Diff: 1
Page Ref: 13.4
32) Which of the following statements is FALSE?
A) The half life of a zero order reaction is dependent on concentration.
B) The half life of a second order reaction is not dependent on concentration.
C) The rate of second order reactions is dependent on concentration.
D) The rate of a first order reaction is dependent on concentraion.
E) None of the statements are FALSE.
Answer: B
Diff: 1
Page Ref: 13.4
33) The rate constant for the first-order decomposition of N 2O is 3.40 s-1. What is the half-life of the
decomposition?
A) 0.491 s
B) 0.204 s
C) 0.236 s
D) 0.424 s
E) 0.294 s
Answer: B
Diff: 2
Page Ref: 13.4
34) The half-life for the second-order decomposition of HI is 15.4 s when the initial concentration of HI
is 0.67 M. What is the rate constant for this reaction?
A) 1.0 × 10-2 M-1s-1
B) 4.5 × 10-2 M-1s-1
C) 9.7 × 10-2 M-1s-1
D) 2.2 × 10-2 M-1s-1
E) 3.8 × 10-2 M-1s-1
Answer: C
Diff: 2
Page Ref: 13.4
35) The half life for the decay of radium is 1620 years. What is the rate constant for this first-order
process?
A) 4.28 × 10-4 yr-1
B) 1.12 × 10-4 yr-1
C) 2.33 × 10-4 yr-1
D) 8.91 × 10-4 yr-1
E) 6.17 × 10-4 yr-1
Answer: A
Diff: 2
Page Ref: 13.4
12
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36) The first-order decomposition of cyclopropane has a rate constant of 6.7 x 10 -4 s-1. If the initial
concentration of cyclopropane is 1.33 M, what is the concentration of cyclopropane after 644 s?
A) 0.43 M
B) 0.15 M
C) 0.94 M
D) 0.86 M
E) 0.67 M
Answer: D
Diff: 3
Page Ref: 13.4
37) The first-order decomposition of N 2O at 1000 K has a rate constant of 0.76 s-1. If the initial
concentration of N 2O is 10.9 M, what is the concentration of N 2O after 9.6 s?
A) 7.4 × 10-3 M
B) 1.0 × 10-3 M
C) 1.4 × 10-3 M
D) 3.6 × 10-3 M
E) 8.7 × 10-3 M
Answer: A
Diff: 3
Page Ref: 13.4
38) The second-order decomposition of HI has a rate constant of 1.80 x 10 -3 M-1s-1. How much HI
remains after 27.3 s if the initial concentration of HI is 4.78 M?
A) 4.55 M
B) 0.258 M
C) 3.87 M
D) 2.20 M
E) 2.39 M
Answer: C
Diff: 3
Page Ref: 13.4
13
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39) Derive an expression for a "1/3-life" for a first-order reaction.
A)
B)
C)
D)
E)
Answer: D
Diff: 3
Page Ref: 13.4
40) Derive an expression for a "1/4-life" for a first-order reaction.
A)
B)
C)
D)
E)
Answer: E
Diff: 3
Page Ref: 13.4
14
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41) The first-order decay of radon has a half-life of 3.823 days. How many grams of radon remain after
7.22 days if the sample initially weighs 250.0 grams?
A) 4.21 g
B) 183 g
C) 54.8 g
D) 76.3 g
E) 67.5 g
Answer: E
Diff: 4
Page Ref: 13.4
42) The first-order decay of radon has a half-life of 3.823 days. How many grams of radon decomposes
after 5.55 days if the sample initially weighs 100.0 grams?
A) 83.4 g
B) 16.6 g
C) 50.0 g
D) 36.6 g
E) 63.4 g
Answer: E
Diff: 4
Page Ref: 13.4
43) The first-order decomposition of N 2O 5 at 328 K has a rate constant of 1.70 × 10-3 s-1. If the initial
concentration of N 2O5 is 2.88 M, what is the concentration of N 2O5 after 12.5 minutes?
A) 0.124 M
B) 0.805 M
C) 2.82 M
D) 0.355 M
E) 0.174 M
Answer: B
Diff: 4
Page Ref: 13.4
44) The second-order decomposition of NO 2 has a rate constant of 0.255 M-1s-1. How much NO 2
decomposes in 4.00 s if the initial concentration of NO 2 (1.00 L volume) is 1.33 M?
A) 1.8 mol
B) 0.85 mol
C) 0.48 mol
D) 0.77 mol
E) 0.56 mol
Answer: D
Diff: 4
Page Ref: 13.4
45) For a reaction, what generally happens if the temperature is increased?
A) a decrease in k occurs, which results in a faster rate
B) a decrease in k occurs, which results in a slower rate
C) an increase in k occurs, which results in a faster rate
D) an increase in k occurs, which results in a slower rate
E) there is no change with k or the rate
Answer: C
Diff: 1
Page Ref: 13.5
15
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46) Identify the rate-determining step.
A) the slowest step
B) the faster step
C) the fast step
D) always the last step
E) always the second step
Answer: A
Diff: 1
Page Ref: 13.5
47) The first-order rearrangement of CH3NC is measured to have a rate constant of 3.61 x 10 -15 s-1 at
298 K and a rate constant of 8.66 × 10-7 s-1 at 425 K. Determine the activation energy for this reaction.
A) 160. kJ/mol
B) 240. kJ/mol
C) 417 kJ/mol
D) 127 kJ/mol
E) 338 kJ/mol
Answer: A
Diff: 3
Page Ref: 13.5
48) A reaction is followed and found to have a rate constant of 3.36 × 10 4 M-1s-1 at 344 K and a rate
constant of 7.69 M-1s-1 at 219 K. Determine the activation energy for this reaction.
A) 23.8 kJ/mol
B) 42.0 kJ/mol
C) 11.5 kJ/mol
D) 12.5 kJ/mol
E) 58.2 kJ/mol
Answer: B
Diff: 3
Page Ref: 13.5
49) A reaction is found to have an activation energy of 108 kJ/mol. If the rate constant for this reaction
is 4.60 × 10-6 s-1 at 275 K, what is the rate constant at 366 K?
A) 12 s-1
B) 1.7 s-1
C) 0.58 s-1
D) 5.4 × 10-5 s-1
E) 1.9 × 10-4 s-1
Answer: C
Diff: 3
Page Ref: 13.5
50) A reaction is found to have an activation energy of 38.0 kJ/mol. If the rate constant for this reaction
is 1.60 × 102 M-1s-1 at 249 K, what is the rate constant at 436 K?
A) 2.38 × 105 M-1s-1
B) 1.26 × 103 M-1s-1
C) 7.94 × 104 M-1s-1
D) 4.20 × 105 M-1s-1
E) 3.80 × 104 M-1s-1
Answer: D
Diff: 3
Page Ref: 13.5
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51) If the activation energy for a given compound is found to be 42.0 kJ/mol, with a frequency factor of
8.0 × 1010 s-1, what is the rate constant for this reaction at 298 K?
A) 2.9 × 10-4 s-1
B) 7.4 × 10-4 s-1
C) 1.4 × 109 s-1
D) 4.6 × 10 5 s-1
E) 3.5 × 103 s-1
Answer: E
Diff: 3
Page Ref: 13.5
52) If the activation energy for a given compound is found to be 103 kJ/mol, with a frequency factor of
4.0 × 1013 s-1, what is the rate constant for this reaction at 398 K?
A) 1.2 s-1
B) 8.2 s-1
C) 3.9 × 1010 s-1
D) 1.7 × 1010 s-1
E) 2.5 × 107 s-1
Answer: A
Diff: 3
Page Ref: 13.5
53) Given the following proposed mechanism, predict the rate law for the overall reaction.
A2 + 2B → 2AB (overall reaction)
Mechanism
A2 ⇌ 2A
A + B → AB
fast
slow
A) Rate = k[A][B]
B) Rate = k[A2][B]
C) Rate = k[A2][B]1/2
D) Rate = k[A2]
E) Rate = k [A2]1/2[B]
Answer: E
Diff: 3
Page Ref: 13.6
54) Which of the following statements is TRUE?
A) The rate constant does not depend on the activation energy for a reaction where the products are
lower in energy than the reactants.
B) A catalyst raises the activation energy of a reaction.
C) Rate constants are temperature dependent.
D) The addition of a homogeneous catalyst does not change the activation energy of a given reaction.
E) None of the above are true.
Answer: C
Diff: 1
Page Ref: 13.7
17
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55) Identify an homogeneous catalyst.
A) SO 2 over vanadium (V) oxide
B) Pd in H2 gas
C) Pt with methane
D) H2SO 4 with concentrated HCl
E) N 2 and H2 catalyzed by Fe
Answer: D
Diff: 1
Page Ref: 13.7
56) Identify an heterogeneous catalyst.
A) CFCs with ozone
B) Pd in H2 gas
C) KI dissolved in H2O2
D) H2SO 4 with concentrated HCl
E) H3PO 4 with an alcohol
Answer: B
Diff: 1
Page Ref: 13.7
57) In the hydrogenation of double bonds, a catalyst is needed. In the first step, the reactants must come
into contact with a metal surface. This step is known as ________.
A) adsorption
B) diffusion
C) reaction
D) desorption
E) none of the above
Answer: A
Diff: 1
Page Ref: 13.7
58) In the hydrogenation of double bonds, a catalyst is needed. In the last step, the reactants must
escape from the surface into the gas phase. This step is known as ________.
A) adsorption
B) diffusion
C) reaction
D) desorption
E) none of the above
Answer: D
Diff: 1
Page Ref: 13.7
59) Biological catalysts that increase the rates of biochemical reactions are known as ________.
A) substrates
B) inhibitors
C) enzymes
D) binders
E) trumanettes
Answer: C
Diff: 1
Page Ref: 13.7
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Algorithmic Questions
1) Given the following balanced equation, determine the rate of reaction with respect to [SO 2].
2 SO 2(g) + O 2(g) → 2 SO 3(g)
A) Rate = B) Rate = +
C) Rate = D) Rate = +
E) It is not possible to determine without more information.
Answer: A
Diff: 2
Page Ref: 13.2
2) Given the following balanced equation, determine the rate of reaction with respect to [O 2].
2 SO 2(g) + O 2(g) → 2 SO 3(g)
A) Rate = B) Rate = +
C) Rate = D) Rate = +
E) It is not possible to determine without more information.
Answer: C
Diff: 2
Page Ref: 13.2
19
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3) Given the following balanced equation, determine the rate of reaction with respect to [SO 3].
2 SO 2(g) + O 2(g) → 2 SO 3(g)
A) Rate = B) Rate = +
C) Rate = D) Rate = E) It is not possible to determine without more information.
Answer: B
Diff: 2
Page Ref: 13.2
4) Given the following balanced equation, determine the rate of reaction with respect to [O 2].
2 O 3(g) → 3 O 2(g)
A) Rate = +
B) Rate = C) Rate = +
D) Rate = E) It is not possible to determine without more information.
Answer: C
Diff: 2
Page Ref: 13.2
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5) Given the following balanced equation, determine the rate of reaction with respect to [H 2].
N 2(g) + 3 H2(g) → 2 NH3(g)
A) Rate = +
B) Rate = C) Rate = +
D) Rate = E) It is not possible to determine without more information.
Answer: D
Diff: 2
Page Ref: 13.2
6) Given the following balanced equation, determine the rate of reaction with respect to [Cl2]. If the
rate of Cl2 loss is 4.24 × 10-2 M/s, what is the rate of formation of NOCl?
2 NO(g) + Cl2(g) → 2 NOCl(g)
A) 4.24 × 10-2 M/s
B) 2.12 × 10-2 M/s
C) 1.06 × 10-1 M/s
D) 8.48 × 10-2 M/s
E) 1.61 × 10-2 M/s
Answer: D
Diff: 3
Page Ref: 13.3
7) Given the following balanced equation, determine the rate of reaction with respect to [Cl2]. If the
rate of Cl2 loss is 4.24 × 10-2 M/s, what is the rate of formation of NO?
2 NO(g) + Cl2(g) → 2 NOCl(g)
A) 4.24 × 10-2 M/s
B) 2.12 × 10-2 M/s
C) 1.06 × 10-1 M/s
D) 8.48 × 10-2 M/s
E) 1.61 × 10-2 M/s
Answer: D
Diff: 3
Page Ref: 13.3
21
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8) Given the following balanced equation, determine the rate of reaction with respect to [O 2]. If the rate
of O 2 loss is 2.64 x 10-3 M/s, what is the rate of formation of SO 3?
2 SO 2(g) + O 2(g) → 2 SO 3(g)
A) 2.64 × 10-3 M/s
B) 1.19 × 10-3 M/s
C) 1.32 × 10-3 M/s
D) 6.60 × 10-2 M/s
E) 5.28 × 10-3 M/s
Answer: E
Diff: 3
Page Ref: 13.3
9) Given the following balanced equation, determine the rate of reaction with respect to [O 2]. If the rate
of formation of O 2 is 7.78 x 10-1 M/s, what is the rate of the loss of O 3?
2 O 3(g) → 3 O 2(g)
A) 0.519 M/s
B) 1.56 M/s
C) 2.34 M/s
D) 1.17 M/s
E) 7.78 M/s
Answer: A
Diff: 3
Page Ref: 13.3
10) What is the overall order of the following reaction, given the rate law?
X+2Y →4Z
Rate = k[X][Y]
A) 3rd order
B) 5th order
C) 2nd order
D) 1st order
E) 6th order
Answer: C
Diff: 2
Page Ref: 13.3
22
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11) What are the units of k in a zero order reaction?
A)
B) M
C) M-1s-1
D)
E)
Answer: A
Diff: 2
Page Ref: 13.3
12) What are the units of k in a first order reaction?
A)
B) M
C) M-1s-1
D)
E)
Answer: E
Diff: 2
Page Ref: 13.3
13) What are the units of k in a second order reaction?
A)
B) M
C) M-1s-1
D)
E)
Answer: C
Diff: 2
Page Ref: 13.3
23
Copyright © 2014 Pearson Education, Inc.
14) The decomposition of dinitrogen pentoxide is described by the chemical equation
2 N2O5(g) → 4 NO 2(g) + O2(g)
If the rate of disappearance of N 2O5 is equal to 1.60 mol/min at a particular moment, what is the rate of
appearance of NO 2 at that moment?
A) 0.800 mol/min
B) 1.60 mol/min
C) 3.20 mol/min
D) 6.40 mol/min
Answer: C
Diff: 3
Page Ref: 13.3
15) What is the overall order of the following reaction, given the rate law?
2X+3Y → 2Z
Rate = k[X]1[Y]2
A) 3rd order
B) 5th order
C) 2nd order
D) 1st order
E) 0th order
Answer: A
Diff: 2
Page Ref: 13.3
16) What is the overall order of the following reaction, given the rate law?
2NO(g) + H2(g) → N 2(g) + 2H2O(g)
Rate = k[NO]2[H2]
A) 1st order
B) 1st order
C) 3rd order
D) 4th order
E) 5th order
Answer: C
Diff: 2
Page Ref: 13.3
17) Given the following rate law, how does the rate of reaction change if the concentration of Y is
doubled?
Rate = k [X][Y]2
A) The rate of reaction will
B) The rate of reaction will
C) The rate of reaction will
D) The rate of reaction will
E) The rate of reaction will
Answer: B
Diff: 2
Page Ref: 13.3
increase by a factor of 2.
increase by a factor of 4.
increase by a factor of 5.
decrease by a factor of 2.
remain unchanged.
24
Copyright © 2014 Pearson Education, Inc.
18) Given the following rate law, how does the rate of reaction change if the concentration of X is
doubled?
Rate = k [X][Y]2
A) The rate of reaction will
B) The rate of reaction will
C) The rate of reaction will
D) The rate of reaction will
E) The rate of reaction will
Answer: A
Diff: 2
Page Ref: 13.3
increase by a factor of 2.
increase by a factor of 3.
increase by a factor of 5.
decrease by a factor of 2.
remain unchanged.
19) Given the following rate law, how does the rate of reaction change if the concentration of Y is
doubled?
Rate = k [X][Y]
A) The rate of reaction will increase by a factor of 2.
B) The rate of reaction will increase by a factor of 4.
C) The rate of reaction willdecrease by a factor of 3.
D) The rate of reaction will decrease by a factor of 2.
E) The rate of reaction will remain unchanged.
Answer: A
Diff: 2
Page Ref: 13.3
20) Given the following rate law, how does the rate of reaction change if the concentration of Y is
doubled?
Rate = k [X]2[Y]3
A) The rate of reaction will increase by a factor of 5.
B) The rate of reaction will increase by a factor of 2.
C) the rate of reaction will increase by a factor of 8.
D) The rate of reaction will increase by a factor of 3.
E) The rate of reaction will remain unchanged.
Answer: C
Diff: 2
Page Ref: 13.3
25
Copyright © 2014 Pearson Education, Inc.
21) Determine the rate law and the value of k for the following reaction using the data provided.
2 N2O5(g) → 4 NO 2(g) + O 2(g)
[ N 2O 5]i (M)
0.093
0.084
0.224
Initial Rate (M-1s-1)
4.84 x 10-4
4.37 x 10-4
1.16 x 10-3
A) Rate = 5.6 × 10-2 M-1s-1[N2O5]2
B) Rate = 6.0 × 10-1 M-2s-1[N2O5]3
C) Rate = 1.6 × 10-3 M1/2s-1[N2O5]1/2
D) Rate = 1.7 × 10-2 M-1/2s-1[N2O5]3/2
E) Rate = 5.2 × 10⁻3 s-1[N 2O5]
Answer: E
Diff: 3
Page Ref: 13.3
22) The decomposition of dinitrogen pentoxide is described by the chemical equation
2 N2O5(g) → 4 NO 2(g) + O2(g)
If the rate of appearance of NO 2 is equal to 0.560 mol/min at a particular moment, what is the rate of
appearance of O 2 at that moment?
A) 0.140 mol/min
B) 0.280 mol/min
C) 1.12 mol/min
D) 2.24 mol/min
Answer: A
Diff: 3
Page Ref: 13.3
23) The decomposition of dinitrogen pentoxide is described by the chemical equation
2 N2O5(g) → 4 NO 2(g) + O2(g)
If the rate of appearance of O 2 is equal to 3.00 mol/min at a particular moment, what is the rate of
disappearance of N 2O5 at that moment?
A) 0.750 mol/min
B) 1.50 mol/min
C) 6.00 mol/min
D) 12.0 mol/min
Answer: C
Diff: 3
Page Ref: 13.3
24) For a reaction that follows the general rate law, Rate = k[A][B]2, what will happen to the rate of
reaction if the concentration of A is increased by a factor of 5.00? The rate will
A) decrease by a factor of 1/25.0.
B) decrease by a factor of 1/5.00.
C) increase by a factor of 5.00.
D) increase by a factor of 25.0.
Answer: C
Diff: 3
Page Ref: 13.3
26
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25) For a reaction that follows the general rate law, Rate = k[A][B]2, what will happen to the rate of
reaction if the concentration of B is increased by a factor of 3.00? The rate will
A) decrease by a factor of 1/9.00.
B) decrease by a factor of 1/3.00.
C) increase by a factor of 3.00.
D) increase by a factor of 9.00.
Answer: D
Diff: 3
Page Ref: 13.3
26) What is the overall reaction order for the reaction that has the rate law: Rate = k[O 2] [NO ]2?
A) zero order
B) first order
C) second order
D) third order
Answer: D
Diff: 3
Page Ref: 13.3
27) Given the following rate law, how does the rate of reaction change if the concentrat ion of X is
doubled?
Rate = k [X]2[Y]3
A) The rate of reaction will increase by a factor of 9.
B) The rate of reaction will increase by a factor of 5.
C) the rate of reaction will increase by a factor of 6.
D) The rate of reaction will increase by a factor of 4.
E) The rate of reaction will remain unchanged.
Answer: D
Diff: 2
Page Ref: 13.3
28) Which of the following represents the equation for a first-order half-life?
A) t 1/2 =
B) t 1/2 =
C) t 1/2 =
D) t 1/2 =
E) t 1/2 =
Answer: B
Diff: 1
Page Ref: 13.4
27
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29) Which of the following represents the equation for a second-order half-life?
A) t 1/2 =
B) t 1/2 =
C) t 1/2 =
D) t 1/2 =
E) t 1/2 =
Answer: A
Diff: 1
Page Ref: 13.4
30) Which of the following represents the equation for a zero-order half-life?
A) t 1/2 =
B) t 1/2 =
C) t 1/2 =
D) t 1/2 =
E) t 1/2 =
Answer: C
Diff: 1
Page Ref: 13.4
31) How many half-lives are required for the concentration of reactant to decrease to 25% of its original
value?
A) 1
B) 4
C) 1.5
D) 3.5
E) 2
Answer: E
Diff: 1
Page Ref: 13.4
28
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32) How many half-lives are required for the concentration of reactant to decrease to 12.5% of its
original value?
A) 3
B) 2
C) 2.5
D) 2.75
E) 8
Answer: A
Diff: 1
Page Ref: 13.4
33) How many half-lives are required for the concentration of reactant to decrease to 1.56% of its
original value?
A) 6
B) 4
C) 24
D) 6.5
E) 7.5
Answer: A
Diff: 1
Page Ref: 13.4
34) If the concentration of a reactant is 6.25%, how many half-lives has it gone through?
A) 7
B) 10
C) 3
D) 4
E) 5
Answer: D
Diff: 1
Page Ref: 13.4
35) The rate constant for a second-order reaction is 0.54 M-1s-1. What is the half-life of this reaction if
the initial concentration is 0.33 M?
A) 0.089 s
B) 1.8 s
C) 0.31 s
D) 5.6 s
E) 1.3 s
Answer: D
Diff: 2
Page Ref: 13.4
36) The rate constant for a first-order reaction is 0.54 M-1s-1. What is the half-life of this reaction if the
initial concentration is 0.33 M?
A) 0.089 s
B) 1.8 s
C) 0.31 s
D) 5.6 s
E) 1.3 s
Answer: E
Diff: 2
Page Ref: 13.4
29
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37) The rate constant for a zero-order reaction is 0.54 M-1s-1. What is the half-life of this reaction if the
initial concentration is 0.33 M?
A) 0.089 s
B) 1.8 s
C) 0.31 s
D) 5.6 s
E) 1.3 s
Answer: C
Diff: 2
Page Ref: 13.4
38) The rate of disappearance of HBr in the gas phase reaction
2HBr(g) → H2(g) + Br2(g)
is 0.301 M
at 150°C. The rate of appearance of Br2 is ________ M s-1.
A) 1.66
B) 0.151
C) 0.0906
D) 0.602
E) 0.549
Answer: B
Diff: 2
Page Ref: 13.4
39) The rate of disappearance of HBr in the gas phase reaction
2HBr(g) → H2(g) + Br2(g)
is 0.130 M s-1 at 150°C. The rate of reaction is ________ M s-1.
A) 3.85
B) 0.0650
C) 0.0169
D) 0.260
E) 0.0860
Answer: B
Diff: 2
Page Ref: 13.4
40) The combustion of ethylene proceeds by the reaction
C2H4(g) + 3O2 (g) → 2CO 2 (g) + 2H2O(g)
When the rate of disappearance of O2 is 0.28 M s-1, the rate of appearance of CO 2 is ________ M s-1.
A) 0.19
B) 0.093
C) 0.84
D) 0.42
E) 0.56
Answer: A
Diff: 2
Page Ref: 13.4
30
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41) The combustion of ethylene proceeds by the reaction
C2H4(g) + 3O2(g) → 2CO2 (g) + 2H2O(g)
When the rate of disappearance of O2 is 0.23 M s-1, the rate of disappearance of C2H4 is
________ M s-1.
A) 0.15
B) 0.077
C) 0.69
D) 0.35
E) 0.46
Answer: B
Diff: 2
Page Ref: 13.4
42) The isomerization of methylisonitrile to acetonitrile
CH3NC(g) → CH3CN(g)
is first order in CH3NC. The rate constant for the reaction is 9.45 × 10 -5 s-1 at 478 K. The half-life of
the reaction when the initial [CH3NC] is 0.030 M is ________ s.
A) 1.06 × 104
B) 5.29 × 103
C) 3.53E × 105
D) 7.33 × 103
E) 1.36 × 10-4
Answer: D
Diff: 3
Page Ref: 13.4
43) The elementary reaction
2NO 2 (g) → 2NO(g) + O2 (g)
is second order in NO2 and the rate constant at 501 K is 7.93 × 10-3 M-1 s-1. The reaction half-life at
this temperature when [NO 2]0 = 0.45 M is ________ s.
A) 3.6 × 10-3
B) 0.011
C) 126
D) 87
E) 280
Answer: E
Diff: 2
Page Ref: 13.4
31
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44) The isomerization of methylisonitrile to acetonitrile
CH3NC(g) → CH3CN(g)
is first order in CH3NC. The half life of the reaction is 5.20 × 101 s at 545 K. The rate constant when the
initial [CH3NC] is 0.030 M is ________ s-1.
A) 75.1
B) 0.641
C) 0.0133
D) 1.56
E) 2.84 × 104
Answer: C
Diff: 2
Page Ref: 13.4
45) The decomposition of N2O5 in solution in carbon tetrachloride proceeds via the reaction
2N2O 5 (soln) → 4NO 2 (soln) + O 2 (soln)
The reaction is first order and has a rate constant of 4.82 × 10-3 s-1 at 64°C. If the reaction is initiated
with 0.058 mol in a 1.00-L vessel, how many moles remain after 151 s?
A) 0.055 M
B) 0.060 M
C) 0.028 M
D) 12 M
E) 2.0 × 103 M
Answer: C
Diff: 2
Page Ref: 13.4
46) SO2Cl2 decomposes in the gas phase by the reaction
SO2Cl2(g) → SO 2(g) + Cl2(g)
The reaction is first order in SO2Cl2 and the rate constant is 3.0 × 10-6 s-1 at 600 K. A vessel is charged
with 2.4 atm of SO 2Cl2 at 600 K. The partial pressure of SO2Cl2 at 3.0 × 105 s is ________ atm.
A) 0.76
B) 2.2
C) 0.98
D) 0.29
E) 1.4 × 105
Answer: C
Diff: 2
Page Ref: 13.4
32
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47) The reaction that occurs in a Breathalyzer, a device used to determine the alcohol level in a person's
bloodstream, is given below. If the rate of appearance of Cr2(SO 4)3 is 1.64 mol/min at a particular
moment, what is the rate of disappearance of C 2H6O at that moment?
2 K2Cr2O 7 + 8 H2SO4 + 3 C2H6O → 2 Cr2(SO 4)3 + 2 K2SO 4 + 11 H2O
A) 0.547 mol/min
B) 1.09 mol/min
C) 2.46 mol/min
D) 4.92 mol/min
Answer: C
Diff: 3
Page Ref: 13.4
48) For a particular first-order reaction, it takes 24 minutes for the concentration of the reactant to
decrease to 25% of its initial value. What is the value for rate constant (in s -1) for the reaction?
A) 2.0 × 10-4 s-1
B) 9.6 × 10-4 s-1
C) 1.2 × 10-2 s-1
D) 5.8 × 10-2 s-1
Answer: B
Diff: 3
Page Ref: 13.4
49) The first-order reaction, SO 2Cl2 → SO 2 + Cl2, has a rate constant equal to 2.20 × 10-5 s-1 at 593
K. What percentage of the initial amount of SO 2Cl2 will remain after 6.00 hours?
A) 1.00%
B) 37.8%
C) 40.2%
D) 62.2%
Answer: D
Diff: 3
Page Ref: 13.4
50) The first-order reaction, 2 N 2O(g) → 2 N 2(g) + O2(g), has a rate constant equal to 0.76 s-1 at 1000
K. How long will it take for the concentration of N 2O to decrease to 12% of its initial concentration?
A) 0.62 s
B) 2.8 s
C) 6.3 s
D) 8.4 s
Answer: B
Diff: 3
Page Ref: 13.4
51) The isomerization reaction, CH3NC → CH3CN, is first order and the rate constant is equal to 0.46
s-1 at 600 K. What is the concentration of CH3NC after 0.20 minutes if the initial concentration is 0.30
M?
A) 1.2 × 10-3 M
B) 2.7 × 10-3 M
C) 1.2 × 10-1 M
D) 2.7 × 10-1 M
Answer: A
Diff: 3
Page Ref: 13.4
33
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52) The following reaction is first order, C 2H6 → 2 CH3. If the rate constant is equal to 5.5 × 10-4 s-1
at 1000 K, how long will it take for 0.35 mol of C 2H6 in a 1.00 L container to decrease to 0.20 mol in
the same container?
A) 4.5 min
B) 17 min
C) 53 min
D) 65 min
Answer: B
Diff: 3
Page Ref: 13.4
53) The rate constant, k, for a first-order reaction is equal to 4.2 × 10-4 s-1. What is the half-life for the
reaction?
A) 2.9 × 10-4 s
B) 1.2 × 103 s
C) 1.7 × 103 s
D) 2.4 × 103 s
Answer: C
Diff: 3
Page Ref: 13.4
54) The first-order reaction, SO 2Cl2 → SO 2 + Cl2, has a half-life of 8.75 hours at 593 K. How long will
it take for the concentration of SO 2Cl2 to fall to 16.5% of its initial value?
A) 0.143 hr
B) 2.28 hr
C) 6.99 hr
D) 22.7 hr
Answer: D
Diff: 3
Page Ref: 13.4
55) For the first-order reaction, 2 N 2O(g) → 2 N 2(g) + O2(g), what is the concentration of N 2O after 3
half-lives if 0.25 mol of N 2O is initially placed into a 1.00-L reaction vessel?
A) 1.6 × 10-2 M
B) 3.1 × 10-2 M
C) 6.2 × 10-2 M
D) 1.2 × 10-1 M
Answer: B
Diff: 3
Page Ref: 13.4
34
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56) Carbon-14, which is present in all living tissue, radioactively decays via a first-order process. A
one-gram sample of wood taken from a living tree gives a rate for carbon-14 decay of 13.6 counts per
minute. If the half-life for carbon-14 is 5720 years, how old is a wood sample that gives a rate for
carbon-14 decay of 11.9 counts per minute?
A) 5.3 × 102 yr
B) 7.6 × 102 yr
C) 1.1 × 103 yr
D) 9.4 × 103 yr
Answer: C
Diff: 3
Page Ref: 13.4
57) In aqueous solution, hypobromite ion, BrO - , reacts to produce bromate ion, BrO 3- , and bromide ion,
Br- , according to the following chemical equation.
3 BrO - (aq) → BrO 3- (aq) + 2 Br- (aq)
A plot of 1/[BrO - ] vs. time is linear and the slope is equal to 0.056 M-1s-1. If the initial concentration of
BrO - is 0.80 M, how long will it take one-half of the BrO - ion to react?
A) 4.5 × 10-2 s
B) 7.1 s
C) 12 s
D) 22 s
Answer: D
Diff: 3
Page Ref: 13.4
58) The second-order reaction 2 Mn(CO)5 → Mn2(CO)10, has a rate constant equal to
3.0 × 109 M-1 s-1 at 25°C. If the initial concentration of Mn(CO)5 is 2.0 × 10-5 M, how long will it
take for 90.% of the reactant to disappear?
A) 6.7 × 10-16 s
B) 7.4 × 10-15 s
C) 1.5 × 10-4 s
D) 6.0 × 103 s
Answer: C
Diff: 3
Page Ref: 13.4
59) Nitrogen dioxide decomposes at 300°C via a second-order process to produce nitrogen monoxide
and oxygen according to the following chemical equation.
2 NO 2(g) → 2 NO(g) + O 2(g).
A sample of NO 2(g) is initially placed in a 2.50-L reaction vessel at 300°C. If the half-life and the rate
constant at 300°C are 11 seconds and 0.54 M-1 s-1, respectively, how many moles of NO 2 were in the
original sample?
A) 0.17 mol
B) 0.42 mol
C) 5.9 mol
D) 15 mol
Answer: B
Diff: 3
Page Ref: 13.4
35
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60) Hydrogen iodide decomposes at 800 K via a second-order process to produce hydrogen and iodine
according to the following chemical equation.
2HI(g) → H2(g) + I2(g)
At 800 K it takes 142 seconds for the initial concentration of HI to decrease from 6.75 × 10 -2 M to 3.50
× 10-2 M. What is the rate constant for the reaction at this temperature?
A) 5.12 × 10-4 M-1s-1
B) 9.69 × 10-2 M-1s-1
C) 10.3 M-1s-1
D) 1.95 × 103 M-1s-1
Answer: B
Diff: 3
Page Ref: 13.4
61) Which of the following reactions would you predict to have the smallest orientation factor?
A) X2 + Y2 → 2 XY
B) NOCl2 + NO → 2 NOCl
C) N 2 + O2 → 2 NO
D) N + O 2 → NO 2
E) All of these reactions should have nearly identical orientation factors.
Answer: B
Diff: 1
Page Ref: 13.5
62) Which of the following reactions would you predict to have the largest orientation factor?
A) NOCl(g) + NOCl(g) → 2NO(g) + Cl2(g)
B) Br2(g) + H2C=CH2(g) → H2BrC-CBrH2(g)
C) NH3(g) + BCl3(g) → H3N-BCl3(g)
D) H(g) + F(g) → HF(g)
E) All of these reactions should have nearly identical orientation factors.
Answer: D
Diff: 1
Page Ref: 13.5
63) The aquation of tris(1,10-phenanthroline)iron(II) in acid solution takes place according to the
equation:
Fe(phen)32+ + 3 H3O+ + 3 H2O → Fe(H2O)62+ + 3 phenH+.
If the activation energy, Ea, is 126 kJ/mol and the rate constant at 30°C is 9.8 × 10-3 min-1, what is the
rate constant at 35°C?
A) 4.4 × 10-3 min-1
B) 2.2 × 10-2 min-1
C) 4.5 × 101 min-1
D) 2.3 × 102 min-1
Answer: B
Diff: 3
Page Ref: 13.5
36
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64) A particular first-order reaction has a rate constant of 1.35 × 102 s-1 at 25.0°C. What is the
magnitude of k at 95.0°C if Ea = 55.5 kJ/mol?
A) 9.56 × 103 s-1
B) 2.85 × 104 s-1
C) 576 s-1
D) 4.33 × 1087 s-1
E) 1.36 × 102 s-1
Answer: A
Diff: 4
Page Ref: 13.5
65) A particular first-order reaction has a rate constant of 1.35 × 102 s-1 at 25.0°C. What is the
magnitude of k at 75.0°C if Ea = 85.6 kJ/mol?
A) 3.47 × 104 s-1
B) 1.92 × 104 s-1
C) 670 s-1
D) 3.85 × 106 s-1
E) 1.36 × 102 s-1
Answer: B
Diff: 4
Page Ref: 13.5
66) Which rate law is termolecular?
A) rate = k[A][B]2
B) rate = k [A][B]3
C) rate = k [A]5
D) rate = k [A][B][C][D]
E) rate = k [A]2
Answer: A
Diff: 1
Page Ref: 13.6
67) Which rate law is bimolecular?
A) rate = k[A][B]3
B) rate = k [A][B]
C) rate = k [A]3
D) rate = k [A][B][C][D]
E) rate = k [A]2[B]2
Answer: B
Diff: 1
Page Ref: 13.6
37
Copyright © 2014 Pearson Education, Inc.
68) Given the following proposed mechanism, predict the rate law for the overall reaction.
2NO 2 + Cl2 → 2NO 2Cl (overall reaction)
Mechanism
NO2 + Cl2 → NO 2Cl + Cl slow
NO2 + Cl → NO 2Cl
fast
A) Rate = k[NO 2][Cl2]
B) Rate = k[NO 2]2[Cl2]2
C) Rate = k[NO 2][Cl]
D) Rate = k[NO 2Cl][Cl]2
E) Rate = k[NO 2Cl]2
Answer: A
Diff: 1
Page Ref: 13.6
Matching Questions
Match the following.
A) activation energy
B) half-life
C) frequency factor
D) reaction order
E) rate constant
1) k
Diff: 1
Page Ref: 13.3
2) n, in Rate = k[A]n
Diff: 1
Page Ref: 13.3
3) t1/2
Diff: 1
Page Ref: 13.4
4) Ea
Diff: 1
Page Ref: 13.5
5) A
Diff: 1
Page Ref: 13.5
Answers: 1) E 2) D 3) B 4) A 5) C
38
Copyright © 2014 Pearson Education, Inc.
Short Answer Questions
1) What happens in the concentration of reactants and products during a chemical reaction?
Answer: The concentration of reactants decrease and the concentration of products increase during a
chemical reaction.
Diff: 1
Page Ref: 13.2
2) What is the difference between average reaction rate and instantaneous reaction rate?
Answer: An average reaction rate is determined using long periods of time during the reaction. An
instantaneous rate is found at a particular moment during reaction. Instantaneous rates usually decrease
during the course of a reaction.
Diff: 1
Page Ref: 13.2
3) Explain how the order of a reaction can be determined.
Answer: The order of a reaction can only be determined experimentally.
Diff: 1
Page Ref: 13.3
4) Define half-life.
Answer: A half-life of a reaction is the time required for the concentration of a reactant to fall to onehalf of its initial value.
Diff: 1
Page Ref: 13.4
5) Define activation energy.
Answer: The activation energy shows the energy of the molecule as the reaction proceeds.
Diff: 1
Page Ref: 13.5
6) Define the frequency factor.
Answer: The frequency factor represents the number of approaches to the activation barrier per unit
time.
Diff: 1
Page Ref: 13.5
7) Explain what the exponential factor in the Arrhenius equation represents.
Answer: The exponential factor depends on both the activation energy of the reaction and the
temperature at which it is done. Using this information, the exponential factor determines what fraction
of collisions will have enough energy to overcome the activation energy and result in products.
Diff: 1
Page Ref: 13.5
8) Is the activation energy for a forward reaction the same as the activation energy for the reverse of the
same reaction? Use a sketch of a reaction energy diagram.
Answer: The relationship between the activation energy of the forward and reverse reactions is related
by the energy difference between the reactants and products. If the reactants are higher in energy than
the products, the activation energy for the forward reaction will be smaller than the activation energy for
the reverse reaction and vice versa. (A sketch showing this relationship should be included).
Diff: 1
Page Ref: 13.6
9) What is a catalyst and what function does it serve?
Answer: A catalyst is a substance that is not used up during a reaction. It also does not affect the
products obtained. A catalyst merely changes the pathway of the reactants to products and in doing so,
reduces the activation energy and speeds up the reaction.
Diff: 1
Page Ref: 13.7
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10) What function do enzymes serve?
Answer: They are biological catalysts. They lower the activation energy of biological processes by
using their three dimensional structure to capture reactants and hold them in a particular orientation that
facilitates reaction.
Diff: 1
Page Ref: 13.7
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