Q: Which unit is appropriate for the rate constant $$k in a $$second-order reaction?

$$\text{M}^{-1}\cdot\text{s}^{-1}$$

Question 1

Which of the following statements best describes the half-life of a first-order reaction?

Accepted Answer

The half-life is constant and independent of the initial concentration.

Question 2

For a reaction following second-order kinetics, which plot yields a straight line?

Accepted Answer

A plot of $$\frac{1}{[A]_t} vs. $$time

Question 3

A radioactive isotope decays according to first-order kinetics. If the rate constant $$k is$$ $$0.0035\ 	ext{yr}^{-1}$$, what is the half-life?

Accepted Answer

$$t_{1/2} = \frac{0.693}{k}$$

Question 4

Which of the following is true for a zeroth-order reaction?

Accepted Answer

The rate is independent of the concentration of the reactant.

Question 5

If the initial concentration of a reactant in a zeroth-order reaction is $$0.10\ 	ext{mol/L}$$ and the rate constant $$k is$$ $$0.02\ 	ext{mol/L}\cdot	ext{min}$$, what is the half-life?

Accepted Answer

$$t_{1/2} = \frac{[A]_0}{2k}$$

Question 6

For a second-order reaction, what happens to the length of each subsequent half-life as the reaction proceeds?

Accepted Answer

Each subsequent half-life becomes longer.

Question 7

Which integrated rate law corresponds to a first-order reaction?

Accepted Answer

$$\ln[A]_t = -kt + \ln[A]_0$$

Question 8

A reaction is found to have a rate law $$	ext{Rate} = k[A]^2. If $$the concentration of $$A is $$doubled, what happens to the rate?

Accepted Answer

The rate quadruples.

Question 9

Which of the following is a diagnostic test for a zeroth-order reaction?

Accepted Answer

A plot of $$[A]_t vs. $$time yields a straight line.

Question 10

In radiocarbon dating, the decay of $$^{14}C to$$ $$^{14}N is an $$example of which type of reaction order?

Accepted Answer

First-order

Question 11

For a first-order reaction, if the rate constant $$k is$$ $$0.271\ 	ext{s}^{-1}$$, what is the half-life?

Accepted Answer

$$t_{1/2} = \frac{0.693}{k}$$

Question 12

Which unit is appropriate for the rate constant $$k in a $$second-order reaction?

Accepted Answer

$$	ext{M}^{-1}\cdot	ext{s}^{-1}$$

Question 13

A reaction has a rate law $$	ext{Rate} = k. $$What is the order of the reaction?

Accepted Answer

Zeroth-order

Question 14

If a plot of $$\ln[A]_t vs. $$time yields a straight line with a negative slope, what can be concluded about the reaction?

Accepted Answer

The reaction is first-order.

Question 15

For a second-order reaction, what is the expression for the half-life?

Accepted Answer

$$t_{1/2} = \frac{1}{k[A]_0}$$

Question 16

Which of the following reactions would be best analyzed using the first-order integrated rate law?

Accepted Answer

Decomposition of ozone catalyzed by atomic chlorine

Question 17

If the concentration of a reactant in a zeroth-order reaction is doubled, what happens to the rate?

Accepted Answer

The rate remains the same.

Question 18

Which equation would you use to determine the concentration of a reactant after a given time in a first-order reaction?

Accepted Answer

$$\ln[A]_t = -kt + \ln[A]_0$$

Question 19

Which of the following best describes the change in half-life for a zeroth-order reaction as the reaction proceeds?

Accepted Answer

Each subsequent half-life becomes shorter.

Chapter 15 Lecture 2

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드