Question 1

A concentration-time study of the gas phase reaction 2 A3 → 3 A2 produced the data in the table below.
Time (s) [A3] (M) [A2] (M) 
0 4) 00 × 10-4 0
10 2.00 × 10-4 3.00 × 10-4
20 1.00 × 10-4 4.50 × 10-4
30 5.00 × 10-5 ?
What is the average rate of formation of A2 in the time interval 20-30 seconds?

Accepted Answer

A)  6) 00 × 10-4 M/s
B)  5) 25 × 10-5 M/s
C)  7) 50 × 10-6 M/s
D)  6) 00 × 10-6 M/sE) A) and B)
F) None of the above

Question 2

Which of the following statements are true about reaction mechanisms?
I.A rate law can be written from the molecularity of the slowest elementary step.
II.The final rate law can include intermediates.
III.The rate of the reaction is dependent on the fastest step in the mechanism.
IV.A mechanism can never be proven to be the correct pathway for a reaction.

Accepted Answer

A)  I,II,III
B)  II,IV
C)  I,III
D)  I,IVE) None of the above
F) B) and D)

Question 3

The reaction below is second order in ClO2 and first order in OH-.When the concentration of ClO2 is 0.020 M and the concentration of OH- is 0.10 M,the initial rate of reaction is 8.00 × 10-4 M/s.What is the rate constant,k,for this reaction?
2 ClO2(aq)+ 2 OH-(aq)→ ClO3-(aq)+ ClO2-(aq)+ H2O(l)

Accepted Answer

Question 4

Consider the first-order reaction A → B in which A molecules (unshaded spheres) are converted to B molecules (shaded spheres) .Given the following pictures at t = 0 seconds and t = 100 seconds,which picture represents the number of A and B molecules remaining at 200 seconds?

Accepted Answer

A)  picture a
B)  picture b
C)  picture c
D)  picture dE) A) and B)
F) All of the above

Question 5

The following reaction is first order in A and first order in B:
A + B → Products Rate = k[A][B]
What is the rate constant k of this reaction in vessel (b) relative to the rate constant k of this reaction in vessel (a) ? Each vessel has the same volume.Shaded spheres represent A molecules,and unshaded spheres represent B molecules.

Accepted Answer

A)  rate constant k in vessel (b) /rate constant k in vessel (a) = 1:2
B)  rate constant k in vessel (b) /rate constant k in vessel (a) = 1:1
C)  rate constant k in vessel (b) /rate constant k in vessel (a) = 2:1
D)  rate constant k in vessel (b) /rate constant k in vessel (a) = 4:1E) All of the above
F) A) and C)

Question 6

Consider a reaction that occurs by the following one-step mechanism:
A2 + B2 → 2 AB
The potential energy profile for this reaction is shown below. 2 + B2 → 2 AB The potential energy profile for this reaction is shown below.   -What is the species present at reaction stage 1? A) an intermediate B) a product C) a reactant D) a transition state" class="answers-bank-image d-inline" rel="preload" >
-What is the species present at reaction stage 1?

Accepted Answer

A)  an intermediate
B)  a product
C)  a reactant
D)  a transition stateE) C) and D)
F) A) and B)

Question 7

The relative initial rates of the reaction A2 + B2 → products in vessels (a) -(d) are 1:1:4:4.Unshaded spheres represent A2 molecules,and shaded spheres represent B2 molecules present at the beginning of the reaction. 2 + B2 → products in vessels (a) -(d) are 1:1:4:4.Unshaded spheres represent A2 molecules,and shaded spheres represent B2 molecules present at the beginning of the reaction.   -What is the overall order of reaction? A) 0 B) 1 C) 2 D) 3" class="answers-bank-image d-inline" rel="preload" >
-What is the overall order of reaction?

Accepted Answer

A)  0
B)  1
C)  2
D)  3E) All of the above
F) A) and D)

Question 8

The decay curve shown below approximates the decay of cobalt-60.What is the approximate half-life of cobalt-60?

Accepted Answer

A)  5 years
B)  12.5 years
C)  15 years
D)  17.5 yearsE) None of the above
F) All of the above

Question 9

For the reaction shown below,if the rate of formation of Br2 is 1.2 × 10-6 M/s,over the same time period the rate of consumption of H+ is ________ M/s.
ClO2-(aq)+ 4 Br-(aq)+ 4 H+(aq)→ Cl-(aq)+ 2 Br2(aq)+2 H2O(l)

Accepted Answer

Question 10

The decomposition of cyclopropane,was observed at 500°C and its concentration was monitored as a function of time.The data set is given below.What is the order of the reaction with respect to cyclopropane?

Accepted Answer

A)  zero
B)  first
C)  second
D)  thirdE) A) and C)
F) C) and D)

Question 11

For the reaction shown below,if the rate of formation of O2 is 6.0 × 10-6 M/s,the rate of decomposition of N2O5 over the same time interval is ________.
2 N2O5(g)→ 4 NO2(g)+ O2(g)

Accepted Answer

Question 12

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 0.10 M?

Accepted Answer

A)  4) 0 x 10-4 M
B)  9) 1 x 10-4 M
C)  4) 0 x 10-2 M
D)  9) 1 x 10-2 ME) B) and C)
F) C) and D)

Question 13

The second-order reaction,2 Mn(CO) 5 → Mn2(CO) 10 has a rate constant equal to 3.0 × 109 M-1s-1 at 25°C.If the initial concentration of Mn(CO) 5 is 1.0 × 10-5 M,how long will it take for 90.% of the reactant to disappear?

Accepted Answer

A)  3) 3 × 10-16 s
B)  3) 7 × 10-15 s
C)  3) 0 × 10-4 s
D)  3) 0 × 103 sE) A) and D)
F) C) and D)

Question 14

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?

Accepted Answer

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-1E) None of the above
F) B) and C)

Question 15

The reaction for the decomposition of dinitrogen monoxide gas to form an oxygen radical is: N2O(g)   →\rarr→  N2(g) + O(g) .If the activation energy is 250 kJ/mol and the frequency factor is 8.0 × 1011 s-1,what is the rate constant for the first-order reaction at 1000 K?

Accepted Answer

A)  1) 1 × 10-3 s-1
B)  7) 0 × 10-2 s-1
C)  1) 6 × 1013 s-1
D)  9) 1 × 1024 s-1 E) C) and D)
F) A) and B)

Question 16

The half life of the reaction shown below is found not to depend on the concentration of H2O2(aq) .
2 H2O2(aq) → 2 H2O(l) + O2(g) 
What is the order of this reaction?

Accepted Answer

A)  zeroth
B)  first
C)  second
D)  thirdE) A) and C)
F) B) and C)

Question 17

The first-order reaction,SO2Cl2 → SO2 + Cl2,has a half-life of 8.75 hours at 593 K.How long will it take for the concentration of SO2Cl2 to fall to 12.5% of its initial value?

Accepted Answer

A)  0) 165 hr
B)  3) 22 hr
C)  6) 06 hr
D)  26.2 hrE) A) and B)
F) A) and C)

Question 18

The hydrolysis of tert-butyl chloride is given in the reaction below:
(CH3) 3CCl(aq) + H2O(l) → (CH3) 3COH(aq) + H+(aq) + Cl-(aq) 
If the rate law is: Rate = k[(CH3) 3CCl],what is the order of the reaction with respect to water?

Accepted Answer

A)  zero
B)  first
C)  second
D)  thirdE) A) and D)
F) B) and C)

Question 19

A reaction has the rate law Rate = k[NO]2[H2].If the concentration of NO is reduced by 1/3,the rate of reaction will be ________ (increased,decreased)by ________.

Accepted Answer

Question 20

Acetaldehyde decomposes at 750 K: CH3CHO → CO + CH4.The reaction is first order in acetaldehyde and the half-life of the reaction is found to be 530 seconds.What is the rate constant for the reaction at this temperature?

Accepted Answer

A)  2) 7 x 10-3 s-1
B)  1) 3 x 10-3 s-1
C)  2) 7 x 102 s-1
D)  7) 6 x 102 s-1E) B) and C)
F) A) and D)

Exam 12: Chemical Kinetics

Correct Answer
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The half life of the reaction shown below is found not to depend on the concentration of H₂O₂(aq) . 2 H₂O₂(aq) → 2 H₂O(l) + O₂(g) What is the order of this reaction?

Correct Answer
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Correct Answer
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For the reaction shown below,if the rate of formation of O₂ is 6.0 × 10^-6M/s,the rate of decomposition of N₂O₅ over the same time interval is ________. 2 N₂O₅(g)→ 4 NO₂(g)+ O₂(g)

Correct Answer
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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 0.10 M?

Correct Answer
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The first-order reaction,SO₂Cl₂ → SO₂ + Cl₂,has a half-life of 8.75 hours at 593 K.How long will it take for the concentration of SO₂Cl₂ to fall to 12.5% of its initial value?

Correct Answer
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For the reaction shown below,if the rate of formation of Br₂ is 1.2 × 10^-6 M/s,over the same time period the rate of consumption of H⁺ is ________ M/s. ClO₂^-(aq)+ 4 Br^-(aq)+ 4 H⁺(aq)→ Cl^-(aq)+ 2 Br₂(aq)+2 H₂O(l)

Correct Answer
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Correct Answer
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Correct Answer
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The second-order reaction,2 Mn(CO) ₅ → Mn₂(CO) ₁₀ has a rate constant equal to 3.0 × 10⁹ M^-1s^-1 at 25°C.If the initial concentration of Mn(CO) ₅ is 1.0 × 10^-5 M,how long will it take for 90.% of the reactant to disappear?

Correct Answer
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Correct Answer
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A reaction has the rate law Rate = k[NO]²[H₂].If the concentration of NO is reduced by 1/3,the rate of reaction will be (increased,decreased)by .

Correct Answer
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Acetaldehyde decomposes at 750 K: CH₃CHO → CO + CH₄.The reaction is first order in acetaldehyde and the half-life of the reaction is found to be 530 seconds.What is the rate constant for the reaction at this temperature?

Correct Answer
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Consider a reaction that occurs by the following one-step mechanism: A₂ + B₂ → 2 AB The potential energy profile for this reaction is shown below. -What is the species present at reaction stage 1?

Correct Answer
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The reaction for the decomposition of dinitrogen monoxide gas to form an oxygen radical is: N₂O(g) $\rarr$ N₂(g) + O(g) .If the activation energy is 250 kJ/mol and the frequency factor is 8.0 × 10¹¹ s^-1,what is the rate constant for the first-order reaction at 1000 K?

Correct Answer
verified

The hydrolysis of tert-butyl chloride is given in the reaction below: (CH₃) ₃CCl(aq) + H₂O(l) → (CH₃) ₃COH(aq) + H⁺(aq) + Cl^-(aq) If the rate law is: Rate = k[(CH₃) ₃CCl],what is the order of the reaction with respect to water?

Correct Answer
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The relative initial rates of the reaction A₂ + B₂ → products in vessels (a) -(d) are 1:1:4:4.Unshaded spheres represent A₂ molecules,and shaded spheres represent B₂ molecules present at the beginning of the reaction. -What is the overall order of reaction?

Correct Answer
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Consider the first-order reaction A → B in which A molecules (unshaded spheres) are converted to B molecules (shaded spheres) .Given the following pictures at t = 0 seconds and t = 100 seconds,which picture represents the number of A and B molecules remaining at 200 seconds?

Correct Answer
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The decay curve shown below approximates the decay of cobalt-60.What is the approximate half-life of cobalt-60?

Correct Answer
verified

The decomposition of cyclopropane,was observed at 500°C and its concentration was monitored as a function of time.The data set is given below.What is the order of the reaction with respect to cyclopropane?

Correct Answer
verified

Exam 12: Chemical Kinetics

The reaction below is second order in ClO2 and first order in OH-.When the concentration of ClO2 is 0.020 M and the concentration of OH- is 0.10 M,the initial rate of reaction is 8.00 × 10-4 M/s.What is the rate constant,k,for this reaction? 2 ClO2(aq)+ 2 OH-(aq)→ ClO3-(aq)+ ClO2-(aq)+ H2O(l)

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The half life of the reaction shown below is found not to depend on the concentration of H2O2(aq) . 2 H2O2(aq) → 2 H2O(l) + O2(g) What is the order of this reaction?

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Correct AnswerverifiedShow Answer

For the reaction shown below,if the rate of formation of O2 is 6.0 × 10-6 M/s,the rate of decomposition of N2O5 over the same time interval is ________. 2 N2O5(g)→ 4 NO2(g)+ O2(g)

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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 0.10 M?

Correct AnswerverifiedShow Answer

The first-order reaction,SO2Cl2 → SO2 + Cl2,has a half-life of 8.75 hours at 593 K.How long will it take for the concentration of SO2Cl2 to fall to 12.5% of its initial value?

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For the reaction shown below,if the rate of formation of Br2 is 1.2 × 10-6 M/s,over the same time period the rate of consumption of H+ is ________ M/s. ClO2-(aq)+ 4 Br-(aq)+ 4 H+(aq)→ Cl-(aq)+ 2 Br2(aq)+2 H2O(l)

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Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

The second-order reaction,2 Mn(CO) 5 → Mn2(CO) 10 has a rate constant equal to 3.0 × 109 M-1s-1 at 25°C.If the initial concentration of Mn(CO) 5 is 1.0 × 10-5 M,how long will it take for 90.% of the reactant to disappear?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

A reaction has the rate law Rate = k[NO]2[H2].If the concentration of NO is reduced by 1/3,the rate of reaction will be ________ (increased,decreased)by ________.

Correct AnswerverifiedShow Answer

Acetaldehyde decomposes at 750 K: CH3CHO → CO + CH4.The reaction is first order in acetaldehyde and the half-life of the reaction is found to be 530 seconds.What is the rate constant for the reaction at this temperature?

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Consider a reaction that occurs by the following one-step mechanism: A2 + B2 → 2 AB The potential energy profile for this reaction is shown below. -What is the species present at reaction stage 1?

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The reaction for the decomposition of dinitrogen monoxide gas to form an oxygen radical is: N2O(g) →\rarr→ N2(g) + O(g) .If the activation energy is 250 kJ/mol and the frequency factor is 8.0 × 1011 s-1,what is the rate constant for the first-order reaction at 1000 K?

Correct AnswerverifiedShow Answer

The hydrolysis of tert-butyl chloride is given in the reaction below: (CH3) 3CCl(aq) + H2O(l) → (CH3) 3COH(aq) + H+(aq) + Cl-(aq) If the rate law is: Rate = k[(CH3) 3CCl],what is the order of the reaction with respect to water?

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The relative initial rates of the reaction A2 + B2 → products in vessels (a) -(d) are 1:1:4:4.Unshaded spheres represent A2 molecules,and shaded spheres represent B2 molecules present at the beginning of the reaction. -What is the overall order of reaction?

Correct AnswerverifiedShow Answer

Consider the first-order reaction A → B in which A molecules (unshaded spheres) are converted to B molecules (shaded spheres) .Given the following pictures at t = 0 seconds and t = 100 seconds,which picture represents the number of A and B molecules remaining at 200 seconds?

Correct AnswerverifiedShow Answer

The decay curve shown below approximates the decay of cobalt-60.What is the approximate half-life of cobalt-60?

Correct AnswerverifiedShow Answer

The decomposition of cyclopropane,was observed at 500°C and its concentration was monitored as a function of time.The data set is given below.What is the order of the reaction with respect to cyclopropane?

Correct AnswerverifiedShow Answer

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The half life of the reaction shown below is found not to depend on the concentration of H₂O₂(aq) . 2 H₂O₂(aq) → 2 H₂O(l) + O₂(g) What is the order of this reaction?

Correct Answer
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Correct Answer
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For the reaction shown below,if the rate of formation of O₂ is 6.0 × 10^-6M/s,the rate of decomposition of N₂O₅ over the same time interval is ________. 2 N₂O₅(g)→ 4 NO₂(g)+ O₂(g)

Correct Answer
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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 0.10 M?

Correct Answer
verified

The first-order reaction,SO₂Cl₂ → SO₂ + Cl₂,has a half-life of 8.75 hours at 593 K.How long will it take for the concentration of SO₂Cl₂ to fall to 12.5% of its initial value?

Correct Answer
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For the reaction shown below,if the rate of formation of Br₂ is 1.2 × 10^-6 M/s,over the same time period the rate of consumption of H⁺ is ________ M/s. ClO₂^-(aq)+ 4 Br^-(aq)+ 4 H⁺(aq)→ Cl^-(aq)+ 2 Br₂(aq)+2 H₂O(l)

Correct Answer
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Correct Answer
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Correct Answer
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The second-order reaction,2 Mn(CO) ₅ → Mn₂(CO) ₁₀ has a rate constant equal to 3.0 × 10⁹ M^-1s^-1 at 25°C.If the initial concentration of Mn(CO) ₅ is 1.0 × 10^-5 M,how long will it take for 90.% of the reactant to disappear?

Correct Answer
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Correct Answer
verified

A reaction has the rate law Rate = k[NO]²[H₂].If the concentration of NO is reduced by 1/3,the rate of reaction will be (increased,decreased)by .

Correct Answer
verified

Acetaldehyde decomposes at 750 K: CH₃CHO → CO + CH₄.The reaction is first order in acetaldehyde and the half-life of the reaction is found to be 530 seconds.What is the rate constant for the reaction at this temperature?

Correct Answer
verified

Consider a reaction that occurs by the following one-step mechanism: A₂ + B₂ → 2 AB The potential energy profile for this reaction is shown below. -What is the species present at reaction stage 1?

Correct Answer
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The reaction for the decomposition of dinitrogen monoxide gas to form an oxygen radical is: N₂O(g) $\rarr$ N₂(g) + O(g) .If the activation energy is 250 kJ/mol and the frequency factor is 8.0 × 10¹¹ s^-1,what is the rate constant for the first-order reaction at 1000 K?

Correct Answer
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The hydrolysis of tert-butyl chloride is given in the reaction below: (CH₃) ₃CCl(aq) + H₂O(l) → (CH₃) ₃COH(aq) + H⁺(aq) + Cl^-(aq) If the rate law is: Rate = k[(CH₃) ₃CCl],what is the order of the reaction with respect to water?

Correct Answer
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The relative initial rates of the reaction A₂ + B₂ → products in vessels (a) -(d) are 1:1:4:4.Unshaded spheres represent A₂ molecules,and shaded spheres represent B₂ molecules present at the beginning of the reaction. -What is the overall order of reaction?

Correct Answer
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Correct Answer
verified

Correct Answer
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Correct Answer
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