Question 1

For the reaction represented below, the experimental rate law is given by rate = k [(CH3) 3CCl]. (CH3) 3CCl(aq) + OH-  →\rarr→ (CH3) 3COH(aq) + Cl- 
 If some solid sodium hydroxide were added to a solution in which [(CH3) 3CCl] = 0.01 M and
[NaOH] = 0.10 M, which of the following would be true? (Assume the temperature and volume remain constant.)

Accepted Answer

A)  Both the reaction rate and k would increase.
B)  Both the reaction rate and k would decrease.
C)  Both the reaction rate and k would remain the same.
D)  The reaction rate would increase but k would remain the same.
E)  The reaction rate would decrease but k would remain the same. F) C) and D)
G) None of the above

Question 2

What is the rate law that corresponds to the data shown for the reaction 2A + B $\rarr$ C?

Accepted Answer

Rate = k[B...

Question 3

At 30°C, by how much is a reaction's activation energy decreased by the addition of a catalyst if the catalyst triples the reaction rate?

Accepted Answer

A)  2.77 kJ/mol
B)  274 J/mol
C)  2.70 J/mol
D)  119 J/mol
E)  1.20 kJ/molF) B) and C)
G) A) and D)

Question 4

The thermal decomposition of acetaldehyde, CH3CHO  →\rarr→ CH4 + CO, is a second-order reaction. The following data were obtained at 518°C. 3CHO  \rarr CH4 + CO, is a second-order reaction. The following data were obtained at 518°C.   Calculate the rate constant for the decomposition of acetaldehyde from the above data. A) 2.2 * 10-3/s B) 0.70 mmHg/s C) 2.2 * 10-3/mmHg·s D) 6.7 * 10-6/mmHg·s E) 5.2 * 10-5/mmHg·s " class="answers-bank-image d-inline" rel="preload" > Calculate the rate constant for the decomposition of acetaldehyde from the above data.

Accepted Answer

A)  2.2 * 10-3/s
B)  0.70 mmHg/s
C)  2.2 * 10-3/mmHg·s
D)  6.7 * 10-6/mmHg·s
E)  5.2 * 10-5/mmHg·s F) A) and E)
G) B) and D)

Question 5

The activation energy for the reaction O + O3  →\rarr→  2O2 is 25 kJ/mol, and the enthalpy change is  Δ\DeltaΔ H = -388 kJ/mol. What is the activation energy for the decomposition of O2 by the reverse reaction?

Accepted Answer

A)  413 kJ
B)  388 kJ
C)  363 kJ
D)  50 kJ
E)  25 kJ F) A) and D)
G) A) and C)

Question 6

Nitrogen pentoxide decomposes by a first-order process yielding N2O4 and oxygen.
2N2O5 $\rarr$ 2N2O4 + O2
 At a given temperature, the half-life of N2O5 is 0.90 hr. What is the first-order rate constant for N2O5 decomposition?

Accepted Answer

0.77 hr<su...

Question 7

At 700 K, the rate constant for the following reaction is 6.2 *10-4 min-1. -4 min-1.   How many minutes are required for 20% of a sample of cyclopropane to isomerize to propene? A) 1,120 min B) 360 min C) 3710 min D) 1.4 * 10-4 min E) 280 min" class="answers-bank-image d-inline" rel="preload" > How many minutes are required for 20% of a sample of cyclopropane to isomerize to propene?

Accepted Answer

A)  1,120 min
B)  360 min
C)  3710 min
D)  1.4 * 10-4 min
E)  280 minF) A) and B)
G) C) and D)

Question 8

The following reaction in aqueous solution was found to be first order in [OH-], first order in [C2H5Br], and inverse first order in Br-.
C2H5Br + OH-   →\rarr→  C2H5OH + Br- 
 Which one of the following mechanisms is consistent with the observed reaction order?

Accepted Answer

A)  C2H5Br  →\rarr→  C2H5+ + Br- - fast C2H5+ + OH-  →\rarr→  C2H5OH slow
B)  C2H5Br +H2O  →\rarr→ C2H5OH + H+ + Br-  slow H+ + OH-  →\rarr→  H2O fast
C)  C2H5Br  →\rarr→ C2H5+ + Br- slow C2H5+ + OH-  →\rarr→ C2H5OH fast
D)  C2H5Br  →\rarr→  C2H5+ + Br-  slow OH- + Br-   →\rarr→  HOBr fastHOBr + C2H5+  →\rarr→  C2H5OH + Br- fast E) A) and D)
F) B) and D)

Question 9

For the following exothermic reaction, the rate law at 298 K is rate = k [H2][I2].
H2(g)+ I2(g)$\rarr$ 2HI(g)
Predict the effect of each of the following changes on the initial rate of the reaction:
a. Addition of hydrogen gas at constant temperature and volume
b. Increase in volume of the reaction vessel at constant temperature
c. Addition of a catalyst
d. Increase in temperature

Accepted Answer

a. The initial rate increases....

Question 10

Which one of the following changes would alter the rate constant (k) for the reaction 2A + B  →\rarr→  products?

Accepted Answer

A)  increasing the concentration of A
B)  increasing the concentration of B
C)  increasing the temperature
D)  measuring k again after the reaction has run for a while E) A) and B)
F) A) and D)

Question 11

For the chemical reaction A  →\rarr→  C, a plot of 1/[A]t versus time was found to give a straight line with a positive slope. What is the order of reaction?

Accepted Answer

A)  zeroth
B)  first
C)  second
D)  Such a plot cannot reveal the order of the reaction. E) B) and C)
F) C) and D)

Question 12

Complete the following statement: A catalyst

Accepted Answer

A)  increases the activation energy.
B)  alters the reaction mechanism.
C)  increases the average kinetic energy of the reactants.
D)  increases the concentration of reactants.
E)  increases the collision frequency of reactant molecules.F) C) and E)
G) A) and E)

Question 13

Which of the following statements is false?

Accepted Answer

A)  A catalyst increases the rate of the forward reaction, but does not alter the reverse rate.
B)  A catalyst alters the mechanism of reaction.
C)  A catalyst alters the activation energy.
D)  A catalyst may be altered in the reaction, but is always regenerated.
E)  A catalyst increases the rate of reaction, but is not consumed.F) A) and B)
G) C) and D)

Question 14

At a particular temperature the first-order gas-phase reaction 2N2O5  →\rarr→ 2N2O4 + O2 has a half-life for the disappearance of dinitrogen pentoxide of 3240 s. If 1.00 atm of N2O5 is introduced into an evacuated 5.00 L flask, what will be the total pressure of the gases in the flask after 1.50 hours?

Accepted Answer

A)  0.685 atm
B)  1.00 atm
C)  0.315 atm
D)  1.68 atm
E)  1.34 atm F) A) and E)
G) A) and B)

Exam 14: Chemical Kinetics

Which one of the following changes would alter the rate constant (k) for the reaction 2A + B $\rarr$ products?

Correct Answer
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Which of the following statements is false?

Correct Answer
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Correct Answer
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The following reaction in aqueous solution was found to be first order in [OH^-], first order in [C₂H₅Br], and inverse first order in Br^-. C₂H₅Br + OH^- $\rarr$ C₂H₅OH + Br^- Which one of the following mechanisms is consistent with the observed reaction order?

Correct Answer
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At 30°C, by how much is a reaction's activation energy decreased by the addition of a catalyst if the catalyst triples the reaction rate?

Correct Answer
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Correct Answer
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Correct Answer
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For the chemical reaction A $\rarr$ C, a plot of 1/[A]_t versus time was found to give a straight line with a positive slope. What is the order of reaction?

Correct Answer
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Nitrogen pentoxide decomposes by a first-order process yielding N₂O₄ and oxygen. 2N₂O₅ $\rarr$ 2N₂O₄ + O₂ At a given temperature, the half-life of N₂O₅ is 0.90 hr. What is the first-order rate constant for N₂O₅ decomposition?

Correct Answer
verified
0.77 hr
View Answer

The activation energy for the reaction O + O₃ $\rarr$ 2O₂ is 25 kJ/mol, and the enthalpy change is $\Delta$ H = -388 kJ/mol. What is the activation energy for the decomposition of O₂ by the reverse reaction?

Correct Answer
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At 700 K, the rate constant for the following reaction is 6.2 *10^-4 min^-1. How many minutes are required for 20% of a sample of cyclopropane to isomerize to propene?

Correct Answer
verified

What is the rate law that corresponds to the data shown for the reaction 2A + B $\rarr$ C? $What is the rate law that corresponds to the data shown for the reaction 2A + B \rarr C?$

Correct Answer
verified
Rate = k[B...
View Answer

Correct Answer
verified
a. The initial rate increases....
View Answer

Complete the following statement: A catalyst

Correct Answer
verified

Exam 14: Chemical Kinetics

Which one of the following changes would alter the rate constant (k) for the reaction 2A + B →\rarr→ products?

Correct AnswerverifiedShow Answer

Which of the following statements is false?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

The following reaction in aqueous solution was found to be first order in [OH-], first order in [C2H5Br], and inverse first order in Br-. C2H5Br + OH- →\rarr→ C2H5OH + Br- Which one of the following mechanisms is consistent with the observed reaction order?

Correct AnswerverifiedShow Answer

At 30°C, by how much is a reaction's activation energy decreased by the addition of a catalyst if the catalyst triples the reaction rate?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

The thermal decomposition of acetaldehyde, CH3CHO →\rarr→ CH4 + CO, is a second-order reaction. The following data were obtained at 518°C. Calculate the rate constant for the decomposition of acetaldehyde from the above data.

Correct AnswerverifiedShow Answer

For the chemical reaction A →\rarr→ C, a plot of 1/[A]t versus time was found to give a straight line with a positive slope. What is the order of reaction?

Correct AnswerverifiedShow Answer

Nitrogen pentoxide decomposes by a first-order process yielding N2O4 and oxygen. 2N2O5 →\rarr→ 2N2O4 + O2 At a given temperature, the half-life of N2O5 is 0.90 hr. What is the first-order rate constant for N2O5 decomposition?

Correct Answerverified0.77 hrView AnswerShow Answer

The activation energy for the reaction O + O3 →\rarr→ 2O2 is 25 kJ/mol, and the enthalpy change is Δ\DeltaΔ H = -388 kJ/mol. What is the activation energy for the decomposition of O2 by the reverse reaction?

Correct AnswerverifiedShow Answer

At 700 K, the rate constant for the following reaction is 6.2 *10-4 min-1. How many minutes are required for 20% of a sample of cyclopropane to isomerize to propene?

Correct AnswerverifiedShow Answer

What is the rate law that corresponds to the data shown for the reaction 2A + B →\rarr→ C?

Correct AnswerverifiedRate = k[B...View AnswerShow Answer

Correct Answerverifieda. The initial rate increases....View AnswerShow Answer

Complete the following statement: A catalyst

Correct AnswerverifiedShow Answer

Which one of the following changes would alter the rate constant (k) for the reaction 2A + B $\rarr$ products?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

The following reaction in aqueous solution was found to be first order in [OH^-], first order in [C₂H₅Br], and inverse first order in Br^-. C₂H₅Br + OH^- $\rarr$ C₂H₅OH + Br^- Which one of the following mechanisms is consistent with the observed reaction order?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

For the chemical reaction A $\rarr$ C, a plot of 1/[A]_t versus time was found to give a straight line with a positive slope. What is the order of reaction?

Correct Answer
verified

Nitrogen pentoxide decomposes by a first-order process yielding N₂O₄ and oxygen. 2N₂O₅ $\rarr$ 2N₂O₄ + O₂ At a given temperature, the half-life of N₂O₅ is 0.90 hr. What is the first-order rate constant for N₂O₅ decomposition?

Correct Answer
verified
0.77 hr
View Answer

The activation energy for the reaction O + O₃ $\rarr$ 2O₂ is 25 kJ/mol, and the enthalpy change is $\Delta$ H = -388 kJ/mol. What is the activation energy for the decomposition of O₂ by the reverse reaction?

Correct Answer
verified

At 700 K, the rate constant for the following reaction is 6.2 *10^-4 min^-1. How many minutes are required for 20% of a sample of cyclopropane to isomerize to propene?

Correct Answer
verified

What is the rate law that corresponds to the data shown for the reaction 2A + B $\rarr$ C? $What is the rate law that corresponds to the data shown for the reaction 2A + B \rarr C?$

Correct Answer
verified
Rate = k[B...
View Answer

Correct Answer
verified
a. The initial rate increases....
View Answer

Correct Answer
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