Question 1

A student analyzed a first-order reaction and obtained the graph below.Unfortunately,the student forgot to label the axes.What are the correct labels for the x and y axes?

Accepted Answer

A)   x axis = time,y axis = ln[A]
B)   x axis = ln[time],y axis = [A]..
C)   x axis = ln[time],y axis = [A]
D)   x axis = time,y axis = 1/[A]
E)   x axis = 1/time,y axis = 1/[A]F) A) and D)
G) A) and C)

Question 2

Which of the following statements is true of the Arrhenius equation?

Accepted Answer

A)   The factor a from the temperature dependence of the rate constant. 
D)   It can be used to calculate the rate constant if   is known. 
E)   The factor   always has a value more than 10." class="answers-bank-image d-inline" rel="preload" > always has a value more than 1.
B)   Ea represents the fraction of molecules having the minimum energy required for a reaction.
C)   It can be used to calculate Ea from the temperature dependence of the rate constant.
D)   It can be used to calculate the rate constant if a from the temperature dependence of the rate constant. 
D)   It can be used to calculate the rate constant if   is known. 
E)   The factor   always has a value more than 10." class="answers-bank-image d-inline" rel="preload" > is known.
E)   The factor a from the temperature dependence of the rate constant. 
D)   It can be used to calculate the rate constant if   is known. 
E)   The factor   always has a value more than 10." class="answers-bank-image d-inline" rel="preload" > always has a value more than 10.F) A) and B)
G) B) and E)

Question 3

For the second-order reaction below,the initial concentration of reactant A is 0.24 M.If the rate constant for the reaction is 1.5 × 10-2 M-1s-1,what is the concentration of A after 265 seconds? 2A → B + C
Rate = k[A]2

Accepted Answer

A)   0.12 M
B)   0.19 M
C)   0.95 M
D)   4.0 M
E)   5.2 MF) B) and C)
G) C) and D)

Question 4

Which of the given relationships correctly compares the rates of the reactants and products for the reaction below? 2 NOCl(g) → 2 NO(g) + Cl2(g)

Accepted Answer

A)   2(g)  
A)     
B)     
C)     
D)     
E)    " class="answers-bank-image d-inline" rel="preload" >
B)   2(g)  
A)     
B)     
C)     
D)     
E)    " class="answers-bank-image d-inline" rel="preload" >
C)   2(g)  
A)     
B)     
C)     
D)     
E)    " class="answers-bank-image d-inline" rel="preload" >
D)   2(g)  
A)     
B)     
C)     
D)     
E)    " class="answers-bank-image d-inline" rel="preload" >
E)   2(g)  
A)     
B)     
C)     
D)     
E)    " class="answers-bank-image d-inline" rel="preload" >F) C) and E)
G) B) and E)

Question 5

The Arrhenius equation, a/R. A)  k2/k1 B)  -Ea C)  ln(k)  D)    E)  1/RT" class="answers-bank-image d-inline" rel="preload" > ,relates the rate constant of reaction and temperature.A plot of ____ versus 1/T will yield a straight line with a slope of -Ea/R.

Accepted Answer

A)   k2/k1
B)   -Ea
C)   ln(k) 
D)   a/R. 
A)   k2/k1 
B)   -Ea 
C)   ln(k)  
D)     
E)   1/RT" class="answers-bank-image d-inline" rel="preload" >
E)   1/RTF) B) and D)
G) B) and C)

Question 6

Which of the following is not a correct representation of the integrated rate expression for a decomposition first-order reaction?

Accepted Answer

A)   
B)   
C)   
D)   
E)   F) C) and D)
G) B) and C)

Question 7

What is the overall order of the reaction NO(g) + O3(g) → NO2(g) + O2(g) if the reaction proceeds via the rate expression given below. 3(g) → NO2(g) + O2(g) if the reaction proceeds via the rate expression given below.   A)  Zero-order B)  First-order C)  Second-order D)  Third-order E)  Fourth-order" class="answers-bank-image d-inline" rel="preload" >

Accepted Answer

A)   Zero-order
B)   First-order
C)   Second-order
D)   Third-order
E)   Fourth-orderF) A) and D)
G) B) and D)

Question 8

The rate constant for a first-order reaction is 1.7 × 10-2 s-1 at 676 K and 3.9 × 10-2 s-1 at 880 K.Determine the activation energy of the reaction.(R = 8.314 J/K⋅mol)

Accepted Answer

A)   8.6 kJ/mol
B)   8.7 kJ/mol
C)   26 kJ/mol
D)   2400 kJ/mol
E)   21 kJ/molF) B) and D)
G) A) and D)

Question 9

Circle the catalyst in the following mechanism.

Accepted Answer

The answer of Circle the catalyst in the following mechanism....

Question 10

For the overall reaction 2A + B → C
Which of the following mechanisms is/are consistent with a rate equation of rate = k[A]2[B]?

Accepted Answer

A)   A + B 2[B]? 
A)   A + B   I (fast)  I + A → C (slow)  
B)   A + B → I (slow)  I + A → C (fast)  
C)   2A → I (slow)  B + I → C (fast)  
D)   2A   I (fast)  I + B → C (slow)  
E)   Answers a and d are both correct." class="answers-bank-image d-inline" rel="preload" > I (fast) I + A → C (slow) 
B)   A + B → I (slow) I + A → C (fast) 
C)   2A → I (slow) B + I → C (fast) 
D)   2A 2[B]? 
A)   A + B   I (fast)  I + A → C (slow)  
B)   A + B → I (slow)  I + A → C (fast)  
C)   2A → I (slow)  B + I → C (fast)  
D)   2A   I (fast)  I + B → C (slow)  
E)   Answers a and d are both correct." class="answers-bank-image d-inline" rel="preload" > I (fast) I + B → C (slow) 
E)   Answers a and d are both correct.F) B) and D)
G) A) and B)

Question 11

For the formation of 1 mol of nitrosyl chloride at a given temperature,ΔrH = -37 kJ/mol. NO(g) + ½ Cl2(g) → NOCl(g) 
The activation energy for this reaction is 81 kJ/mol.What is the activation energy for the reverse reaction?

Accepted Answer

A)   81 kJ/mol
B)   44 kJ/mol
C)   118 kJ/mol
D)   -37 kJ/mol
E)   -118 kJ/molF) B) and C)
G) D) and E)

Question 12

A first-order reaction is 40.0% complete at the end of 48.6 minutes.What is the value of the rate constant?

Accepted Answer

A)   1.89 × 10-2 min-1
B)   1.05 × 10-2 min-1
C)   53.0 min-1
D)   95.1 min-1
E)   none of theseF) A) and C)
G) None of the above

Question 13

For which of the following hypothetical rate laws would the units of the rate constant have the general form M-1·h−1?

Accepted Answer

A)   Reaction rate = k[A]2
B)   Reaction rate = k
C)   Reaction rate = k[A]..
D)   Reaction rate = k[A]
E)   Reaction rate = k[A]4F) D) and E)
G) All of the above

Question 14

The rate law for a reaction is rate = k[A]2[B].Which of the following mixtures of reactants will give the smallest initial rate?

Accepted Answer

A)   1.0 M A and 1.0 M B
B)   2.0 M A and 0.50 M B
C)   0.50 M A and 0.50 M B
D)   0.125 M A and 3.0 M B
E)   1.5 M A and 0.50 M BF) A) and B)
G) All of the above

Question 15

Below is a proposed mechanism for the decomposition of H2O2. H2O2 + I- → H2O + IO-
Slow
H2O2 + IO- → H2O + O2 + I-
Fast
Which of the following statements is incorrect?

Accepted Answer

A)   IO- is a catalyst.
B)   I- is a catalyst.
C)   The net reaction is 2H2O2 → 2H2O + O2.
D)   The reaction is first-order with respect to [I-].
E)   The reaction is first-order with respect to [H2O2].F) A) and B)
G) D) and E)

Question 16

What is the name given to a substance that increases the rate of a chemical reaction but is not itself consumed?

Accepted Answer

A)   catalyst
B)   reactant
C)   intermediate
D)   enthalpy
E)   rate constantF) All of the above
G) B) and D)

Question 17

How many mechanistic steps are depicted by in this potential energy diagram?

Accepted Answer

A)   one step
B)   two steps
C)   three steps
D)   four steps
E)   five stepsF) B) and D)
G) C) and E)

Question 18

For the hypothetical reaction aA → products,the experimental data showed the following behavior (below) .What is the reaction order with respect to reactant A?

Accepted Answer

A)   zero order
B)   first order
C)   second order
D)   third order
E)   fourth orderF) C) and D)
G) A) and B)

Question 19

The reaction A → B follows first-order kinetics with a half-life of 21.7 hours.If the concentration of A is 0.023 M after 48.0 hours,what was the initial concentration of A?

Accepted Answer

A)   0.0050 M
B)   0.051 M
C)   0.51 M
D)   0.11 M
E)   2.0 MF) A) and B)
G) C) and E)

Question 20

The rate constant at 366 K for a first-order reaction is 7.7 × 10-3 s-1 and the activation energy is 15.9 kJ/mol.What is the value of the frequency factor,A,in the Arrhenius equation? (R = 8.314 J/K⋅mol)

Accepted Answer

A)   0.0047 s-1
B)   0.70 s-1
C)   0.93 s-1
D)   1.1 s-1
E)   1.4 s-1F) A) and B)
G) B) and E)

Exam 15: Chemical Kinetics: the Rates of Chemical Reactions

For the formation of 1 mol of nitrosyl chloride at a given temperature,ΔrH = -37 kJ/mol. NO(g) + ½ Cl2(g) → NOCl(g) The activation energy for this reaction is 81 kJ/mol.What is the activation energy for the reverse reaction?

Correct AnswerverifiedShow Answer

A student analyzed a first-order reaction and obtained the graph below.Unfortunately,the student forgot to label the axes.What are the correct labels for the x and y axes?

Correct AnswerverifiedShow Answer

The Arrhenius equation, ,relates the rate constant of reaction and temperature.A plot of ____ versus 1/T will yield a straight line with a slope of -Ea/R.

Correct AnswerverifiedShow Answer

What is the overall order of the reaction NO(g) + O3(g) → NO2(g) + O2(g) if the reaction proceeds via the rate expression given below.

Correct AnswerverifiedShow Answer

How many mechanistic steps are depicted by in this potential energy diagram?

Correct AnswerverifiedShow Answer

Which of the following is not a correct representation of the integrated rate expression for a decomposition first-order reaction?

Correct AnswerverifiedShow Answer

The rate constant at 366 K for a first-order reaction is 7.7 × 10-3 s-1 and the activation energy is 15.9 kJ/mol.What is the value of the frequency factor,A,in the Arrhenius equation? (R = 8.314 J/K⋅mol)

Correct AnswerverifiedShow Answer

Which of the given relationships correctly compares the rates of the reactants and products for the reaction below? 2 NOCl(g) → 2 NO(g) + Cl2(g)

Correct AnswerverifiedShow Answer

Circle the catalyst in the following mechanism.

Correct AnswerverifiedShow Answer

What is the name given to a substance that increases the rate of a chemical reaction but is not itself consumed?

Correct AnswerverifiedShow Answer

For which of the following hypothetical rate laws would the units of the rate constant have the general form M-1·h−1?

Correct AnswerverifiedShow Answer

The rate law for a reaction is rate = k[A]2[B].Which of the following mixtures of reactants will give the smallest initial rate?

Correct AnswerverifiedShow Answer

The rate constant for a first-order reaction is 1.7 × 10-2 s-1 at 676 K and 3.9 × 10-2 s-1 at 880 K.Determine the activation energy of the reaction.(R = 8.314 J/K⋅mol)

Correct AnswerverifiedShow Answer

The reaction A → B follows first-order kinetics with a half-life of 21.7 hours.If the concentration of A is 0.023 M after 48.0 hours,what was the initial concentration of A?

Correct AnswerverifiedShow Answer

Which of the following statements is true of the Arrhenius equation?

Correct AnswerverifiedShow Answer

For the hypothetical reaction aA → products,the experimental data showed the following behavior (below) .What is the reaction order with respect to reactant A?

Correct AnswerverifiedShow Answer

For the overall reaction 2A + B → C Which of the following mechanisms is/are consistent with a rate equation of rate = k[A]2[B]?

Correct AnswerverifiedShow Answer

Below is a proposed mechanism for the decomposition of H2O2. H2O2 + I- → H2O + IO- Slow H2O2 + IO- → H2O + O2 + I- Fast Which of the following statements is incorrect?

Correct AnswerverifiedShow Answer

For the second-order reaction below,the initial concentration of reactant A is 0.24 M.If the rate constant for the reaction is 1.5 × 10-2 M-1s-1,what is the concentration of A after 265 seconds? 2A → B + C Rate = k[A]2

Correct AnswerverifiedShow Answer

A first-order reaction is 40.0% complete at the end of 48.6 minutes.What is the value of the rate constant?

Correct AnswerverifiedShow Answer

For the formation of 1 mol of nitrosyl chloride at a given temperature,Δ_rH = -37 kJ/mol. NO(g) + ½ Cl₂(g) → NOCl(g) The activation energy for this reaction is 81 kJ/mol.What is the activation energy for the reverse reaction?

Correct Answer
verified

Correct Answer
verified

The Arrhenius equation, ,relates the rate constant of reaction and temperature.A plot of ____ versus 1/T will yield a straight line with a slope of -E_a/R.

Correct Answer
verified

What is the overall order of the reaction NO(g) + O₃(g) → NO₂(g) + O₂(g) if the reaction proceeds via the rate expression given below.

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

The rate constant at 366 K for a first-order reaction is 7.7 × 10^-3 s^-1 and the activation energy is 15.9 kJ/mol.What is the value of the frequency factor,A,in the Arrhenius equation? (R = 8.314 J/K⋅mol)

Correct Answer
verified

Which of the given relationships correctly compares the rates of the reactants and products for the reaction below? 2 NOCl(g) → 2 NO(g) + Cl₂(g)

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

The rate law for a reaction is rate = k[A]²[B].Which of the following mixtures of reactants will give the smallest initial rate?

Correct Answer
verified

The rate constant for a first-order reaction is 1.7 × 10^-2 s^-1 at 676 K and 3.9 × 10^-2 s^-1 at 880 K.Determine the activation energy of the reaction.(R = 8.314 J/K⋅mol)

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

For the overall reaction 2A + B → C Which of the following mechanisms is/are consistent with a rate equation of rate = k[A]²[B]?

Correct Answer
verified

Below is a proposed mechanism for the decomposition of H₂O₂. H₂O₂ + I^- → H₂O + IO^- Slow H₂O₂ + IO^- → H₂O + O₂ + I^- Fast Which of the following statements is incorrect?

Correct Answer
verified

For the second-order reaction below,the initial concentration of reactant A is 0.24 M.If the rate constant for the reaction is 1.5 × 10^-2 M^-1s^-1,what is the concentration of A after 265 seconds? 2A → B + C Rate = k[A]²

Correct Answer
verified

Correct Answer
verified