Question 1

Substitute natural gas can be synthesized by passing carbon monoxide and hydrogen over Ni or Co at 400°C.  This process is an example of homogeneous catalysis.

Accepted Answer

A) True 
 B)False

Question 2

For the overall chemical reaction shown below, which one of the following statements can be rightly assumed? 2H2S(g) + O2(g) \9\rarr\)  2S(s) + 2H2O(l)

Accepted Answer

A)  The reaction is third-order overall.
B)  The reaction is second-order overall.
C)  The rate law is, rate = k[H2S]2 [O2].
D)  The rate law is, rate = k[H2S] [O2].
E)  The rate law cannot be determined from the information given.F) All of the above
G) C) and D)

Question 3

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) C) and E)
G) B) and E)

Question 4

The gas phase reaction of nitrogen dioxide and carbon monoxide was found experimentally to be second-order with respect to NO2, and zero-order with respect to CO below 25°C. NO2 + CO  →\rarr→  NO + CO2
 Which one of the following mechanisms is consistent with the observed reaction order?

Accepted Answer

A)  NO2 + 2CO 2, and zero-order with respect to CO below 25°C. NO2 + CO  \rarr  NO + CO2  Which one of the following mechanisms is consistent with the observed reaction order? 
A)  NO2 + 2CO   N + 2CO2 fast N + NO2  \rarr  2NO slow 
B)  NO2 + 2CO  \rarr N + 2CO2 slow N + NO2  \rarr  2NO fast 
C)  NO2 + NO2  \rarr  NO3 + NO fast NO3 + CO  \rarr NO2 + CO2 slow 
D)  NO2 + NO2  \rarr  NO3 + NO slow NO3 + CO  \rarr NO2 + CO2 fast " class="answers-bank-image d-inline" rel="preload" > N + 2CO2 fast N + NO2  →\rarr→  2NO slow
B)  NO2 + 2CO  →\rarr→ N + 2CO2 slow N + NO2  →\rarr→  2NO fast
C)  NO2 + NO2  →\rarr→  NO3 + NO fast NO3 + CO  →\rarr→ NO2 + CO2 slow
D)  NO2 + NO2  →\rarr→  NO3 + NO slow NO3 + CO  →\rarr→ NO2 + CO2 fast E) A) and D)
F) C) and D)

Question 5

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) All of the above
G) B) and E)

Question 6

The rate constant for the first-order decomposition of C4H8 at 500°C is 9.2 × 10-3 s-1.How long will it take for 10.0% of a 0.100 M sample of C4H8 to decompose at 500°C?

Accepted Answer

Question 7

It is possible for the following overall reaction to consist of a one step mechanism:
2A $\rarr$ products

Accepted Answer

A) True 
 B)False

Question 8

The reaction A + 2B  →\rarr→  products has been found to have the rate law, rate = k[A] [B]2.While holding the concentration of A constant, the concentration of B is increased from x to 3x.Predict by what factor the rate of reaction increases.

Accepted Answer

A)  3
B)  6
C)  9
D)  27
E)  30 F) A) and E)
G) A) and D)

Question 9

For the reaction BrO3- + 5Br-+ 6H+  →\rarr→  3Br2 + 3H2O at a particular time, - Δ\DeltaΔ [BrO3-]/ Δ\DeltaΔ t = 1.5 × 10-2 M/s.What is - Δ\DeltaΔ [Br-]/ Δ\DeltaΔ t at the same instant?

Accepted Answer

A)  13 M/s
B)  7.5 × 10-2 M/s
C)  1.5 × 10-2 M/s
D)  3.0 × 10-3 M/s
E)  330 M/s F) A) and D)
G) A) and C)

Question 10

Nitrous oxide (N2O) decomposes at 600°C according to the balanced equation 2N2O(g)  →\rarr→ 2N2(g) + O2(g) 
A reaction mechanism involving three steps is shown below.Identify all of the catalysts in the following mechanism.
Cl2(g)  →\rarr→  2Cl(g) 
N2O(g) + Cl(g)  →\rarr→ N2(g) + ClO(g) (occurs twice) 
ClO(g) + ClO(g)  →\rarr→ Cl2(g) + O2(g)

Accepted Answer

A)  Cl
B)  Cl2
C)  ClO
D)  N2O
E)  ClO and Cl F) None of the above
G) B) and E)

Question 11

At a certain temperature, the data below were collected for the reaction below.
2ICl + H2 $\rarr$I2 + 2HCl.
Determine the rate constant for the reaction.

Accepted Answer

Question 12

The rate determining step must be the first step of a reaction mechanism in all cases.

Accepted Answer

A) True 
 B)False

Question 13

When acetaldehyde at a pressure of 364 mmHg is introduced into an evacuated 500.mL flask at 518°C, the half-life for the second-order decomposition process, CH3CHO  →\rarr→  CH4 + CO, is 410.s.What will the total pressure in the flask be after 1.00 hour?

Accepted Answer

A)  327 mmHg
B)  654 mmHg
C)  37 mmHg
D)  691 mmHg
E)  728 mmHg F) All of the above
G) A) and E)

Question 14

The first-order decomposition, A  →\rarr→  products, has a rate constant of 0.150 s-1.Starting with [A]o = 0.350 M, how much time is required for [A]t = 0.125 M?

Accepted Answer

A)  6.86 s
B)  2.98 s
C)  34 s
D)  1.50 s
E)  4.62 s F) A) and D)
G) All of the above

Question 15

A reaction was experimentally determined to follow the rate law, Rate = k[A] where k = 0.15 s-1.Starting with [A]o = 0.225M, how many seconds will it take for [A]t = 0.0350M

Accepted Answer

A)  3.4 x 10-2 s
B)  5.3 x 10-3 s
C)  12 s
D)  160 s
E)  1.3 sF) B) and E)
G) C) and D)

Question 16

In general, to calculate the activation energy for an elementary step given the rate constants at two different temperatures, which equation should be used?

Accepted Answer

A)  ln([A]t/[A]o) = - kt
B)  t1/2 = ln2/k
C)  ln(k1/k2) = Ea/R( (T1 - T2) /T1T2) 
D)  1/[A]t = kt + 1/[A]o
E)  Rate = k[A]F) A) and E)
G) A) and B)

Question 17

The reaction A + 2B  →\rarr→  products has the rate law, rate = k[A][B]3.If the concentration of B is doubled while that of A is unchanged, by what factor will the rate of reaction increase?

Accepted Answer

A)  2
B)  4
C)  6
D)  8
E)  9 F) A) and E)
G) C) and E)

Question 18

An increase in the temperature of the reactants causes an increase in the rate of reaction.The best explanation for this behavior is that as the temperature increases,

Accepted Answer

A)  the concentration of reactants increases.
B)  the activation energy decreases.
C)  the collision frequency increases.
D)  the fraction of collisions with total kinetic energy greater than Ea increases.
E)  the activation energy increases.F) A) and E)
G) B) and C)

Question 19

The reaction C4H10  →\rarr→  C2H6 + C2H4 has an activation energy (Ea) of 350 kJ/mol, and the Ea of the reverse reaction is 260 kJ/mol.Estimate  Δ\DeltaΔ H, in kJ/mol, for the reaction as written above.

Accepted Answer

A)  -90 kJ/mol
B)  +90 kJ/mol
C)  350 kJ/mol
D)  -610 kJ/mol
E)  +610 kJ/mol F) A) and B)
G) A) and C)

Question 20

A nuclear stress test utilizes a gamma-emitting radioisotope such as thallium-201 to follow the flow of blood through the heart - first at rest, and then under stress.The first-order rate constant for the decay of thallium-201 is 9.5 x 10-3 hr-1.Calculate how long it takes for the amount of thallium-201 to fall to 5.0% of its original value.

Accepted Answer

Exam 13: Chemical Kinetics

Correct Answer
verified

Substitute natural gas can be synthesized by passing carbon monoxide and hydrogen over Ni or Co at 400°C. This process is an example of homogeneous catalysis.

Correct Answer
verified

An increase in the temperature of the reactants causes an increase in the rate of reaction.The best explanation for this behavior is that as the temperature increases,

Correct Answer
verified

The rate determining step must be the first step of a reaction mechanism in all cases.

Correct Answer
verified

The reaction A + 2B $\rarr$ products has been found to have the rate law, rate = k[A] [B]².While holding the concentration of A constant, the concentration of B is increased from x to 3x.Predict by what factor the rate of reaction increases.

Correct Answer
verified

The gas phase reaction of nitrogen dioxide and carbon monoxide was found experimentally to be second-order with respect to NO₂, and zero-order with respect to CO below 25°C. NO₂ + CO $\rarr$ NO + CO₂ Which one of the following mechanisms is consistent with the observed reaction order?

Correct Answer
verified

In general, to calculate the activation energy for an elementary step given the rate constants at two different temperatures, which equation should be used?

Correct Answer
verified

It is possible for the following overall reaction to consist of a one step mechanism: 2A $\rarr$ products

Correct Answer
verified

The reaction A + 2B $\rarr$ products has the rate law, rate = k[A][B]³.If the concentration of B is doubled while that of A is unchanged, by what factor will the rate of reaction increase?

Correct Answer
verified

When acetaldehyde at a pressure of 364 mmHg is introduced into an evacuated 500.mL flask at 518°C, the half-life for the second-order decomposition process, CH₃CHO $\rarr$ CH₄ + CO, is 410.s.What will the total pressure in the flask be after 1.00 hour?

Correct Answer
verified

The reaction C₄H₁₀ $\rarr$ C₂H₆ + C₂H₄ has an activation energy (E_a) of 350 kJ/mol, and the E_a of the reverse reaction is 260 kJ/mol.Estimate $\Delta$ H, in kJ/mol, for the reaction as written above.

Correct Answer
verified

For the overall chemical reaction shown below, which one of the following statements can be rightly assumed? 2H₂S(g) + O₂(g) \9\rarr\) 2S(s) + 2H₂O(l)

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

Correct Answer
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For the reaction BrO₃^-+ 5Br^-+ 6H⁺ $\rarr$ 3Br₂ + 3H₂O at a particular time, - $\Delta$ [BrO₃^-]/ $\Delta$ t = 1.5 × 10^-2 M/s.What is - $\Delta$ [Br^-]/ $\Delta$ t at the same instant?

Correct Answer
verified

Correct Answer
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The rate constant for the first-order decomposition of C₄H₈ at 500°C is 9.2 × 10^-3 s^-1.How long will it take for 10.0% of a 0.100 M sample of C₄H₈ to decompose at 500°C?

Correct Answer
verified

A reaction was experimentally determined to follow the rate law, Rate = k[A] where k = 0.15 s^-1.Starting with [A]_o = 0.225M, how many seconds will it take for [A]_t = 0.0350M

Correct Answer
verified

The first-order decomposition, A $\rarr$ products, has a rate constant of 0.150 s^-1.Starting with [A]_o = 0.350 M, how much time is required for [A]_t = 0.125 M?

Correct Answer
verified

Correct Answer
verified

Exam 13: Chemical Kinetics

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

Substitute natural gas can be synthesized by passing carbon monoxide and hydrogen over Ni or Co at 400°C. This process is an example of homogeneous catalysis.

Correct AnswerverifiedShow Answer

An increase in the temperature of the reactants causes an increase in the rate of reaction.The best explanation for this behavior is that as the temperature increases,

Correct AnswerverifiedShow Answer

The rate determining step must be the first step of a reaction mechanism in all cases.

Correct AnswerverifiedShow Answer

The reaction A + 2B →\rarr→ products has been found to have the rate law, rate = k[A] [B]2.While holding the concentration of A constant, the concentration of B is increased from x to 3x.Predict by what factor the rate of reaction increases.

Correct AnswerverifiedShow Answer

The gas phase reaction of nitrogen dioxide and carbon monoxide was found experimentally to be second-order with respect to NO2, and zero-order with respect to CO below 25°C. NO2 + CO →\rarr→ NO + CO2 Which one of the following mechanisms is consistent with the observed reaction order?

Correct AnswerverifiedShow Answer

In general, to calculate the activation energy for an elementary step given the rate constants at two different temperatures, which equation should be used?

Correct AnswerverifiedShow Answer

It is possible for the following overall reaction to consist of a one step mechanism: 2A →\rarr→ products

Correct AnswerverifiedShow Answer

The reaction A + 2B →\rarr→ products has the rate law, rate = k[A][B]3.If the concentration of B is doubled while that of A is unchanged, by what factor will the rate of reaction increase?

Correct AnswerverifiedShow Answer

When acetaldehyde at a pressure of 364 mmHg is introduced into an evacuated 500.mL flask at 518°C, the half-life for the second-order decomposition process, CH3CHO →\rarr→ CH4 + CO, is 410.s.What will the total pressure in the flask be after 1.00 hour?

Correct AnswerverifiedShow Answer

The reaction C4H10 →\rarr→ C2H6 + C2H4 has an activation energy (Ea) of 350 kJ/mol, and the Ea of the reverse reaction is 260 kJ/mol.Estimate Δ\DeltaΔ H, in kJ/mol, for the reaction as written above.

Correct AnswerverifiedShow Answer

For the overall chemical reaction shown below, which one of the following statements can be rightly assumed? 2H2S(g) + O2(g) \9\rarr\) 2S(s) + 2H2O(l)

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

Correct AnswerverifiedShow Answer

For the reaction BrO3- + 5Br-+ 6H+ →\rarr→ 3Br2 + 3H2O at a particular time, - Δ\DeltaΔ [BrO3-]/ Δ\DeltaΔ t = 1.5 × 10-2 M/s.What is - Δ\DeltaΔ [Br-]/ Δ\DeltaΔ t at the same instant?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

The rate constant for the first-order decomposition of C4H8 at 500°C is 9.2 × 10-3 s-1.How long will it take for 10.0% of a 0.100 M sample of C4H8 to decompose at 500°C?

Correct AnswerverifiedShow Answer

A reaction was experimentally determined to follow the rate law, Rate = k[A] where k = 0.15 s-1.Starting with [A]o = 0.225M, how many seconds will it take for [A]t = 0.0350M

Correct AnswerverifiedShow Answer

The first-order decomposition, A →\rarr→ products, has a rate constant of 0.150 s-1.Starting with [A]o = 0.350 M, how much time is required for [A]t = 0.125 M?

Correct AnswerverifiedShow Answer

At a certain temperature, the data below were collected for the reaction below. 2ICl + H2 →\rarr→ I2 + 2HCl. Determine the rate constant for the reaction.

Correct AnswerverifiedShow Answer

Correct Answer
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Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

The reaction A + 2B $\rarr$ products has been found to have the rate law, rate = k[A] [B]².While holding the concentration of A constant, the concentration of B is increased from x to 3x.Predict by what factor the rate of reaction increases.

Correct Answer
verified

The gas phase reaction of nitrogen dioxide and carbon monoxide was found experimentally to be second-order with respect to NO₂, and zero-order with respect to CO below 25°C. NO₂ + CO $\rarr$ NO + CO₂ Which one of the following mechanisms is consistent with the observed reaction order?

Correct Answer
verified

Correct Answer
verified

It is possible for the following overall reaction to consist of a one step mechanism: 2A $\rarr$ products

Correct Answer
verified

The reaction A + 2B $\rarr$ products has the rate law, rate = k[A][B]³.If the concentration of B is doubled while that of A is unchanged, by what factor will the rate of reaction increase?

Correct Answer
verified

When acetaldehyde at a pressure of 364 mmHg is introduced into an evacuated 500.mL flask at 518°C, the half-life for the second-order decomposition process, CH₃CHO $\rarr$ CH₄ + CO, is 410.s.What will the total pressure in the flask be after 1.00 hour?

Correct Answer
verified

The reaction C₄H₁₀ $\rarr$ C₂H₆ + C₂H₄ has an activation energy (E_a) of 350 kJ/mol, and the E_a of the reverse reaction is 260 kJ/mol.Estimate $\Delta$ H, in kJ/mol, for the reaction as written above.

Correct Answer
verified

For the overall chemical reaction shown below, which one of the following statements can be rightly assumed? 2H₂S(g) + O₂(g) \9\rarr\) 2S(s) + 2H₂O(l)

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

Correct Answer
verified

For the reaction BrO₃^-+ 5Br^-+ 6H⁺ $\rarr$ 3Br₂ + 3H₂O at a particular time, - $\Delta$ [BrO₃^-]/ $\Delta$ t = 1.5 × 10^-2 M/s.What is - $\Delta$ [Br^-]/ $\Delta$ t at the same instant?

Correct Answer
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Correct Answer
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The rate constant for the first-order decomposition of C₄H₈ at 500°C is 9.2 × 10^-3 s^-1.How long will it take for 10.0% of a 0.100 M sample of C₄H₈ to decompose at 500°C?

Correct Answer
verified

A reaction was experimentally determined to follow the rate law, Rate = k[A] where k = 0.15 s^-1.Starting with [A]_o = 0.225M, how many seconds will it take for [A]_t = 0.0350M

Correct Answer
verified

The first-order decomposition, A $\rarr$ products, has a rate constant of 0.150 s^-1.Starting with [A]_o = 0.350 M, how much time is required for [A]_t = 0.125 M?

Correct Answer
verified

Correct Answer
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