Question 1

What is the rate law for the following reaction and its mechanism? 
2O3 → 3O2 (overall reaction)
O3 → O2 + Oσ (Slow)
O∙ + O3 → 2O2 (Fast)

Accepted Answer

A)  Rate = k[O3] 
B)  Rate = k[O3]2 
C)  Rate = k[O3]2/[O2] 
D)  Rate = k[O3]/[O2] 
E)  Rate = k[O3][O2] 
A)  Rate = k[O3] 
B)  Rate = k[O3]2 
C)  Rate = k[O3]2/[O2] 
D)  Rate = k[O3]/[O2] 
E)  Rate = k[O3][O2]

Question 2

The correct units of the specific rate constant for a zero order reaction are ________.

Accepted Answer

A)  L/mol-sec 
B)  sec-1 
C)  sec 
D)  L2/mol2sec 
E)  rate is a constant, so it has no units 
A)  L/mol-sec 
B)  sec-1 
C)  sec 
D)  L2/mol2sec 
E)  rate is a constant, so it has no units

Question 3

The rate of a specific chemical reaction is independent of the concentrations of the reactants. Thus the reaction is:

Accepted Answer

A)  first order in A 
B)  second order 
C)  first order in the product 
D)  catalyzed 
E)  overall zero order 
A)  first order in A 
B)  second order 
C)  first order in the product 
D)  catalyzed 
E)  overall zero order

Question 4

If the rate of a specific chemical reaction is independent of the concentrations of the reactants, the reaction is zero order.

Accepted Answer

A) True 
 B)False

Question 5

If the half-life of a reactant is independent of its initial concentration, the reaction order is ________.

Accepted Answer

A)  0 
B)  0.5 
C)  1 
D)  2 
E)  3 
A)  0 
B)  0.5 
C)  1 
D)  2 
E)  3

Question 6

What is the rate law for the following mechanism? CH3COOC2H5 + H2O → CH3COOC2H6+ + OH- (Slow)
CH3COOC2H6+ → CH3COOH + C2H5+ (Fast)
C2H5+ + OH- → C2H5OH (Fast)

Accepted Answer

A)  Rate = k[CH3COOC2H5][H2O]2 
B)  Rate = k[C2H5OH] 
C)  Rate = k[CH3COOH] 
D)  Rate = k[CH3COOC2H5] 
E)  Rate = k[CH3COOC2H5][H2O] 
A)  Rate = k[CH3COOC2H5][H2O]2 
B)  Rate = k[C2H5OH] 
C)  Rate = k[CH3COOH] 
D)  Rate = k[CH3COOC2H5] 
E)  Rate = k[CH3COOC2H5][H2O]

Question 7

For the second-order reaction A → products, the following data are obtained: [A] = 3.024 M, t = 0 min
[A] = 2.935 M, t = 1.0 min
[A] = 2.852 M, t = 2.0 min
What is the concentration of [A] after 4 min?

Accepted Answer

A)  2.70 M 
B)  2.68 M 
C)  0.76 M 
D)  2.76 M 
E)  2.62 M 
A)  2.70 M 
B)  2.68 M 
C)  0.76 M 
D)  2.76 M 
E)  2.62 M

Question 8

Calculate rate constant k for a first order reaction with a half-life of 75.0 min.

Accepted Answer

A)  52.0 min-1 
B)  1.54 × 10-4 min-1 
C)  1.33 × 10-2 min-1 
D)  9.24 × 10-3 min-1 
E)  2.67 × 10-2 min-1 
A)  52.0 min-1 
B)  1.54 × 10-4 min-1 
C)  1.33 × 10-2 min-1 
D)  9.24 × 10-3 min-1 
E)  2.67 × 10-2 min-1

Question 9

For the reaction: 2NO2(g) → 2NO(g) + O2(g) concentration-time data are: 
 
What is the order of the reaction with respect to [NO2]?

Accepted Answer

A)  zero 
B)  first 
C)  second 
D)  third 
E)  2 + 2 
A)  zero 
B)  first 
C)  second 
D)  third 
E)  2 + 2

Question 10

Data for the reaction A + B → C are given below. What is the correct rate law?

Accepted Answer

A)  k [A] [B] 
B)  k [A]2 [B] 
C)  k [A]2 [B]2 
D)  k [B]2 
E)  k[A]2 
A)  k [A] [B] 
B)  k [A]2 [B] 
C)  k [A]2 [B]2 
D)  k [B]2 
E)  k[A]2

Question 11

For the reaction: 2N2O5(g) → 4NO2(g) + O2(g) the rate law is:   = k[N2O5] At 300 K, the half-life is 2.50 × 104 seconds and the activation energy is 103.3 kJ/mol O2. What is the half-life at 350 K?

Accepted Answer

A)  67.3 s 
B)  9.3 × 106 s 
C)  1.09 × 10-17 s 
D)  2.48 × 104 s 
E)  0.145 s 
A)  67.3 s 
B)  9.3 × 106 s 
C)  1.09 × 10-17 s 
D)  2.48 × 104 s 
E)  0.145 s

Question 12

For the reaction: A → Products concentration-time data are: [A]t 0.2000 0.1486 0.1182 0.0981 0.0839 M
T 0 1 2 3 4 h
[A]t 0.0733 0.0650 0.0584 0.0531 0.0486 M
T 5 6 7 8 9 h
What is the order of this reaction with respect to [A]?

Accepted Answer

A)  zero 
B)  first 
C)  second 
D)  third 
E)  none of these 
A)  zero 
B)  first 
C)  second 
D)  third 
E)  none of these

Question 13

For the reaction: C2H4Br2 + 3 KI → C2H4 + 2 KBr + KI3, when the rate of reaction is 2.0 × 10-5, what is the rate of disappearance of C2H4Br2?

Accepted Answer

A)  -0.67 × 10-5 
B)  -2.0 × 10-5 
C)  -4.0 × 10-5 
D)  -6.0 × 10-5 
E)  -1.0 × 10-5 
A)  -0.67 × 10-5 
B)  -2.0 × 10-5 
C)  -4.0 × 10-5 
D)  -6.0 × 10-5 
E)  -1.0 × 10-5

Question 14

Choose the INCORRECT answer. The rate of a chemical reaction:

Accepted Answer

A)  usually is increased when the concentration of one of the reactants is increased 
B)  is dependent on temperature 
C)  may be increased by certain catalytic agents 
D)  will be very rapid if the activation energy is large 
E)  describes the change in concentration of a reactant or product with time 
A)  usually is increased when the concentration of one of the reactants is increased 
B)  is dependent on temperature 
C)  may be increased by certain catalytic agents 
D)  will be very rapid if the activation energy is large 
E)  describes the change in concentration of a reactant or product with time

Question 15

For a reaction Rate = k[A][B]2, what factor will keep k unchanged?

Accepted Answer

A)  raising temperature 
B)  adding inhibitor 
C)  increasing [A] 
D)  adding catalyst 
A)  raising temperature 
B)  adding inhibitor 
C)  increasing [A] 
D)  adding catalyst

Question 16

A factor that decreases the activation energy for a reaction: 
I. decreases the rate constant
II. increases the rate constant
III. has no effect on the rate constant
IV. makes the product yield increase
V. might be a catalyst

Accepted Answer

A)  I and IV 
B)  II and IV 
C)  I, IV, and V 
D)  IV and III 
E)  II and V 
A)  I and IV 
B)  II and IV 
C)  I, IV, and V 
D)  IV and III 
E)  II and V

Question 17

A reaction is first order. If its initial rate is 0.0200 M/s and 25.0 days later its rate is 6.25 × 10-4 M/s, then its half-life is ________.

Accepted Answer

A)  12.5 days 
B)  5.0 days 
C)  25.0 days 
D)  50.0 days 
E)  2.5 days 
A)  12.5 days 
B)  5.0 days 
C)  25.0 days 
D)  50.0 days 
E)  2.5 days

Question 18

Activation energy is: I) the minimum kinetic energy required for each molecule in a collision to produce a reaction.
II) the minimum total kinetic energy required for the molecules in a collision to produce a reaction.
III) a factor in determining the rate of a reaction.
IV) high for fast reactions.

Accepted Answer

A)  I and III 
B)  I, III, and IV 
C)  II, III 
D)  II and IV 
E)  II, III, and IV 
A)  I and III 
B)  I, III, and IV 
C)  II, III 
D)  II and IV 
E)  II, III, and IV

Question 19

For the second order reaction A → products, the following data are obtained: [A] = 1.512 M, t = 0 min
[A] = 1.490 M, t = 1.0 min
[A] = 1.469 M, t = 2.0 min
What is the concentration of [A] in the experiment after 4.0 min for the reaction?

Accepted Answer

A)  1.43 M 
B)  1.35 M 
C)  1.61 M 
D)  1.40 M 
E)  1.37 M 
A)  1.43 M 
B)  1.35 M 
C)  1.61 M 
D)  1.40 M 
E)  1.37 M

Question 20

For the second order reaction A → products, the following data are obtained: [A] = 1.512 M, t = 0 min
[A] = 1.490 M, t = 1.0 min
[A] = 1.469 M, t = 2.0 min
What is the rate constant, k, for the reaction?

Accepted Answer

A)  3.6 × 10-3 M-1 min-1 
B)  1.4 × 10-2 M-1 min-1 
C)  2.2 × 10-2 M-1 min-1 
D)  1.0 × 10-2 M-1 min-1 
E)  9.7 × 10-3 M-1 min-1 
A)  3.6 × 10-3 M-1 min-1 
B)  1.4 × 10-2 M-1 min-1 
C)  2.2 × 10-2 M-1 min-1 
D)  1.0 × 10-2 M-1 min-1 
E)  9.7 × 10-3 M-1 min-1

Exam 14: Chemical Kinetics

What is the rate law for the following reaction and its mechanism? 2O3 → 3O2 (overall reaction) O3 → O2 + Oσ (Slow) O∙ + O3 → 2O2 (Fast)

The correct units of the specific rate constant for a zero order reaction are ________.

The rate of a specific chemical reaction is independent of the concentrations of the reactants. Thus the reaction is:

If the rate of a specific chemical reaction is independent of the concentrations of the reactants, the reaction is zero order.

If the half-life of a reactant is independent of its initial concentration, the reaction order is ________.

What is the rate law for the following mechanism? CH3COOC2H5 + H2O → CH3COOC2H6+ + OH- (Slow) CH3COOC2H6+ → CH3COOH + C2H5+ (Fast) C2H5+ + OH- → C2H5OH (Fast)

For the second-order reaction A → products, the following data are obtained: [A] = 3.024 M, t = 0 min [A] = 2.935 M, t = 1.0 min [A] = 2.852 M, t = 2.0 min What is the concentration of [A] after 4 min?

Calculate rate constant k for a first order reaction with a half-life of 75.0 min.

For the reaction: 2NO2(g) → 2NO(g) + O2(g) concentration-time data are: What is the order of the reaction with respect to [NO2]?

Data for the reaction A + B → C are given below. What is the correct rate law?

For the reaction: 2N2O5(g) → 4NO2(g) + O2(g) the rate law is: = k[N2O5] At 300 K, the half-life is 2.50 × 104 seconds and the activation energy is 103.3 kJ/mol O2. What is the half-life at 350 K?

For the reaction: A → Products concentration-time data are: [A]t 0.2000 0.1486 0.1182 0.0981 0.0839 M T 0 1 2 3 4 h [A]t 0.0733 0.0650 0.0584 0.0531 0.0486 M T 5 6 7 8 9 h What is the order of this reaction with respect to [A]?

For the reaction: C2H4Br2 + 3 KI → C2H4 + 2 KBr + KI3, when the rate of reaction is 2.0 × 10-5, what is the rate of disappearance of C2H4Br2?

Choose the INCORRECT answer. The rate of a chemical reaction:

For a reaction Rate = k[A][B]2, what factor will keep k unchanged?

A factor that decreases the activation energy for a reaction: I. decreases the rate constant II. increases the rate constant III. has no effect on the rate constant IV. makes the product yield increase V. might be a catalyst

A reaction is first order. If its initial rate is 0.0200 M/s and 25.0 days later its rate is 6.25 × 10-4 M/s, then its half-life is ________.

For the second order reaction A → products, the following data are obtained: [A] = 1.512 M, t = 0 min [A] = 1.490 M, t = 1.0 min [A] = 1.469 M, t = 2.0 min What is the concentration of [A] in the experiment after 4.0 min for the reaction?

For the second order reaction A → products, the following data are obtained: [A] = 1.512 M, t = 0 min [A] = 1.490 M, t = 1.0 min [A] = 1.469 M, t = 2.0 min What is the rate constant, k, for the reaction?

Matter - Its Properties and Measurement

Atoms and the Atomic Theory

Chemical Compounds

Chemical Reactions

Introduction to Reactions in Aqueous Solutions

Gases

Thermochemistry

Electrons in Atoms

The Periodic Table and Some Atomic Properties

Chemical Bonding I: Basic Concepts

Chemical Bonding II: Additional Aspects

Intermolecular Forces: Liquids and Solids

Solutions and Their Physical Properties

Principles of Chemical Equilibrium

Acids and Bases

Additional Aspects of Acid-Base Equilibria

Solubility and Complex-Ion Equilibria

Spontaneous Change: Entropy and Free Energy

Electrochemistry

Main Group Elements I: Groups 1, 2, 13, and 14

Main Group Elements II: Groups 18, 17, 16, 15, and Hydrogen

The Transition Elements

Complex Ions and Coordination Compounds

Nuclear Chemistry 1-41

Structures of Organic Compounds

Reactions of Organic Compounds

Chemistry of the Living State

Filters

What is the rate law for the following reaction and its mechanism? 2O₃ → 3O₂ (overall reaction) O₃ → O₂ + Oσ (Slow) O∙ + O₃→ 2O₂ (Fast)

What is the rate law for the following mechanism? CH₃COOC₂H₅ + H₂O → CH₃COOC₂H₆⁺ + OH- (Slow) CH₃COOC₂H₆⁺ → CH₃COOH + C₂H₅+ (Fast) C₂H₅⁺ + OH- → C2H5OH (Fast)

For the reaction: 2NO₂(g) → 2NO(g) + O₂(g) concentration-time data are: What is the order of the reaction with respect to [NO₂]?

For the reaction: 2N₂O₅(g) → 4NO₂(g) + O₂(g) the rate law is: = k[N₂O₅] At 300 K, the half-life is 2.50 × 10⁴ seconds and the activation energy is 103.3 kJ/mol O₂. What is the half-life at 350 K?

For the reaction: C₂H₄Br₂+ 3 KI → C₂H₄ + 2 KBr + KI₃, when the rate of reaction is 2.0 × 10^-5, what is the rate of disappearance of C₂H₄Br₂?

A reaction is first order. If its initial rate is 0.0200 M/s and 25.0 days later its rate is 6.25 × 10^-4 M/s, then its half-life is ________.