Q: For the reaction $$aA + bB \rightarrow cC + dD$$, the general rate expression is:

$$\text{rate} = \frac{1}{a} \frac{\Delta [A]}{\Delta t} = -\frac{1}{b} \frac{\Delta [B]}{\Delta t} = \frac{1}{c} \frac{\Delta [C]}{\Delta t} = \frac{1}{d} \frac{\Delta [D]}{\Delta t}$$

Q: In the reaction $$2 NO_2$ (g) \rightarrow 2 NO (g) + O_2$ (g)$$, if the rate of disappearance of $$NO_2 is$$ $$8.6 \times 10$$^{-6}$$ mol L$$^{-1}$$ s$$^{-1}$$, what is the rate of formation of O_2$?

$$4.3 \times 10$$^{-6}$$ mol L$$^{-1}$$ s$$^{-1}$$

Q: For the reaction $$2 $$HgCl_2$$ + C_2O_4$$^{2-}$$ \rightarrow 2 Cl^- + 2 CO_2$ + Hg_2Cl_2$$, if the rate law is $$\text{rate} = k[$$HgCl_2$$]$$, what are the units of the rate constant $$k$$?

$$\text{mol L}^{-1} \text{s}^{-1}$$

Q: Which of the following best describes the units of the rate constant $$k$$ for a second-order reaction?

$$\text{mol}^{-1} \text{L} \text{s}^{-1}$$

Question 1

Which of the following best describes the field of chemical kinetics?

Accepted Answer

The study of the speed or rate at which chemical reactions occur.

Question 2

Given the reaction $$A \rightarrow B$$ and the following data:

Time (min): 0, 20, 40

$$[A] ($$mol L$$^{-1}$$): 1.00, 0.54, 0.30

$$[B] ($$mol L$$^{-1}$$): 0, 0.46, 0.70

What is the average rate of formation of B between 0 and 20 minutes?

Accepted Answer

$$0.023$$ mol L$$^{-1}$$ min$$^{-1}$$

Question 3

Which factor does NOT affect the rate of a chemical reaction?

Accepted Answer

Color of the reactants

Question 4

For the reaction $$aA + bB \rightarrow cC + dD$$, the general rate expression is:

Accepted Answer

$$	ext{rate} = \frac{1}{a} \frac{\Delta [A]}{\Delta t} = -\frac{1}{b} \frac{\Delta [B]}{\Delta t} = \frac{1}{c} \frac{\Delta [C]}{\Delta t} = \frac{1}{d} \frac{\Delta [D]}{\Delta t}$$

Question 5

By convention, reaction rates are always reported as:

Accepted Answer

Positive values

Question 6

In the reaction $$2 NO_2$ (g) ightarrow 2 NO (g) + O_2$ (g)$$, if the rate of disappearance of $$NO_2 is$$ $$8.6 	imes 10$$^{-6}$$ mol L$$^{-1}$$ s$$^{-1}$$, what is the rate of formation of O_2$?

Accepted Answer

$$4.3 	imes 10$$^{-6}$$ mol L$$^{-1}$$ s$$^{-1}$$

Question 7

The rate law for the reaction $$NH_4^+ (aq$$) + $$NO_2^- (aq$$) ightarrow $$N_2 (g) + 2 H_2O (l$$)$$ is $$	ext{rate} = k[$$NO_2$$^-][$$NH_4$$^+]$$. What is the overall order of the reaction?

Accepted Answer

Second order

Question 8

Which statement about reaction orders is TRUE?

Accepted Answer

Reaction orders are determined experimentally and do not necessarily match the balanced equation coefficients.

Question 9

If doubling the concentration of reactant A causes the rate to quadruple, what is the order of the reaction with respect to A?

Accepted Answer

Second order

Question 10

For the reaction $$2 $$HgCl_2$$ + C_2O_4$$^{2-}$$ ightarrow 2 Cl^- + 2 CO_2$ + Hg_2Cl_2$$, if the rate law is $$	ext{rate} = k[$$HgCl_2$$]$$, what are the units of the rate constant $$k$$?

Accepted Answer

$$	ext{mol L}^{-1} 	ext{s}^{-1}$$

Question 11

A graph of concentration vs. time for a zero-order reaction is:

Accepted Answer

A straight line with a negative slope

Question 12

For a first-order reaction, the integrated rate law is:

Accepted Answer

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

Question 13

If a plot of $$\ln [A] vs. $$time gives a straight line, what is the order of the reaction?

Accepted Answer

First order

Question 14

For a second-order reaction with one reactant, the rate law is:

Accepted Answer

$$	ext{rate} = k[A]^2$$

Question 15

Which of the following is a real-world example of a zero-order reaction?

Accepted Answer

Metabolism of alcohol in the human body

Question 16

If the rate law for a reaction is $$	ext{rate} = k[A][B]$$, what is the overall order of the reaction?

Accepted Answer

Second order

Question 17

For a reaction where the rate law is $$	ext{rate} = k[A]^0$$, what happens to the rate if the concentration of A is doubled?

Accepted Answer

The rate remains unchanged

Question 18

Which of the following best describes the units of the rate constant $$k$$ for a second-order reaction?

Accepted Answer

$$	ext{mol}^{-1} 	ext{L} 	ext{s}^{-1}$$

Question 19

A reaction has a rate law $$	ext{rate} = k[A]^2[B]. If $$the concentration of A is tripled and B is doubled, by what factor does the rate increase?

Accepted Answer

18

Question 20

Which of the following statements about integrated and differential rate laws is correct?

Accepted Answer

Integrated rate laws express how concentrations depend on time.

Chapter 13: Chemical Kinetics – Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards