Q: For the reaction $$2\text{N}_2\text{O} \rightarrow 2\text{N}_2 + \text{O}_2$$, which of the following correctly expresses the rate in terms of the change in concentration of $$\text{N}_2\text{O}$$?

$$\text{Rate} = -\frac{1}{2} \frac{\Delta [\text{N}_2\text{O}]}{\Delta t}$$

Q: Given the reaction $$2\text{A} + \text{B} \rightarrow 2\text{C}$$, if $$\frac{\Delta [\text{B}]}{\Delta t} = -0.0125\ \text{M} \cdot \text{s}^{-1}$$, what is $$\frac{\Delta [\text{A}]}{\Delta t}$$?

$$-0.025\ \text{M} \cdot \text{s}^{-1}$$

Q: For the reaction $$\text{A} \rightarrow \text{Products}$$, the following data were collected: $$\begin{align*} \text{Time (s)} & 0 & 20 & 40 & 60 & 80 \\ [\text{A}] (\text{M}) & 1.0 & 0.8 & 0.6 & 0.4 & 0.2 \\ \end{align*}$$ What is the average rate of disappearance of A between 0 and 40 seconds?

$$0.01\ \text{M} \cdot \text{s}^{-1}$$

Q: A reaction has the rate law $$\text{Rate} = k[\text{Y}]^2. If$$ $$k = 0.011\ \text{M}^{-1} \cdot \text{s}^{-1}$$ and $$[\text{Y}] = 0.50\ \text{M}$$, what is the rate?

$$0.00275\ \text{M} \cdot \text{s}^{-1}$$

Q: A reaction is first order in A and second order in B. Which of the following is the correct rate law?

$$\text{Rate} = k[\text{A}][\text{B}]^2$$

Q: In a laboratory, a student observes that the rate of a reaction is $$0.0080\ \text{M} \cdot \text{s}^{-1}$$ when $$[\text{N}_2\text{O}]$$ decreases by $$0.016\ \text{M}$$ over 2 seconds. What is the correct rate expression for this reaction?

$$\text{Rate} = -\frac{1}{2} \frac{\Delta [\text{N}_2\text{O}]}{\Delta t}$$

Question 1

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

Accepted Answer

The rate increases by a factor of 12.

Question 2

For the reaction $$2	ext{N}_2	ext{O} ightarrow 2	ext{N}_2 + 	ext{O}_2$$, which of the following correctly expresses the rate in terms of the change in concentration of $$	ext{N}_2	ext{O}$$?

Accepted Answer

$$	ext{Rate} = -\frac{1}{2} \frac{\Delta [	ext{N}_2	ext{O}]}{\Delta t}$$

Question 3

A reaction has a rate law $$	ext{Rate} = k. $$Which of the following statements is true about this reaction?

Accepted Answer

The reaction is zero order with respect to all reactants.

Question 4

Given the reaction $$2	ext{A} + 	ext{B} ightarrow 2	ext{C}$$, if $$\frac{\Delta [	ext{B}]}{\Delta t} = -0.0125\ 	ext{M} \cdot 	ext{s}^{-1}$$, what is $$\frac{\Delta [	ext{A}]}{\Delta t}$$?

Accepted Answer

$$-0.025\ 	ext{M} \cdot 	ext{s}^{-1}$$

Question 5

A student measures the rate of a reaction and finds that doubling the concentration of reactant X does not change the rate. What is the order of the reaction with respect to X?

Accepted Answer

Zero order

Question 6

For the reaction $$	ext{A} ightarrow 	ext{Products}$$, the following data were collected:

$$\begin{align*}
	ext{Time (s)} & 0 & 20 & 40 & 60 & 80 \
[	ext{A}] (	ext{M}) & 1.0 & 0.8 & 0.6 & 0.4 & 0.2 \
\end{align*}$$

What is the average rate of disappearance of A between 0 and 40 seconds?

Accepted Answer

$$0.01\ 	ext{M} \cdot 	ext{s}^{-1}$$

Question 7

A reaction has the rate law $$	ext{Rate} = k[	ext{Y}]^2. If$$ $$k = 0.011\ 	ext{M}^{-1} \cdot 	ext{s}^{-1}$$ and $$[	ext{Y}] = 0.50\ 	ext{M}$$, what is the rate?

Accepted Answer

$$0.00275\ 	ext{M} \cdot 	ext{s}^{-1}$$

Question 8

In a real-world scenario, the decomposition of hydrogen peroxide ($$2	ext{H}_2	ext{O}_2 ightarrow 2	ext{H}_2	ext{O} + 	ext{O}_2) is $$catalyzed in the presence of manganese dioxide. If the rate law is $$	ext{Rate} = k[	ext{H}_2	ext{O}_2]$$, what will happen to the rate if the concentration of $$	ext{H}_2	ext{O}_2 is $$halved?

Accepted Answer

The rate will be halved.

Question 9

A reaction is first order in A and second order in B. Which of the following is the correct rate law?

Accepted Answer

$$	ext{Rate} = k[	ext{A}][	ext{B}]^2$$

Question 10

In a laboratory, a student observes that the rate of a reaction is $$0.0080\ 	ext{M} \cdot 	ext{s}^{-1}$$ when $$[	ext{N}_2	ext{O}]$$ decreases by $$0.016\ 	ext{M}$$ over 2 seconds. What is the correct rate expression for this reaction?

Accepted Answer

$$	ext{Rate} = -\frac{1}{2} \frac{\Delta [	ext{N}_2	ext{O}]}{\Delta t}$$

Question 11

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

Accepted Answer

The rate increases by a factor of 12.

Question 12

Which of the following best describes a zero-order reaction?

Accepted Answer

The rate is independent of the concentration of reactants.

Question 13

In a medical context, the breakdown of a drug in the body follows first-order kinetics. If the half-life of the drug is 4 hours, how much of a 200 mg dose remains after 8 hours?

Accepted Answer

50 mg

Question 14

A reaction has the rate law $$	ext{Rate} = k[	ext{A}]^0. If$$ $$k = 0.011\ 	ext{M} \cdot 	ext{s}^{-1}$$, what is the rate when $$[	ext{A}] = 0.5\ 	ext{M}$$?

Accepted Answer

$$0.011\ 	ext{M} \cdot 	ext{s}^{-1}$$

Question 15

For the reaction $$2	ext{A} + 	ext{B} ightarrow 2	ext{C}$$, if $$\frac{\Delta [	ext{C}]}{\Delta t} = 0.013\ 	ext{M} \cdot 	ext{s}^{-1}$$, what is $$\frac{\Delta [	ext{A}]}{\Delta t}$$?

Accepted Answer

$$-0.025\ 	ext{M} \cdot 	ext{s}^{-1}$$

Question 16

A reaction is found to be second order overall. Which of the following could be a possible rate law?

Accepted Answer

$$	ext{Rate} = k[	ext{A}][	ext{B}]$$

Question 17

In a real-world environmental scenario, the photodecomposition of ozone ($$2	ext{O}_3 ightarrow 3	ext{O}_2) is $$found to be zero order. What will happen to the rate if the concentration of ozone is doubled?

Accepted Answer

The rate will remain unchanged.

Question 18

A reaction has the rate law $$	ext{Rate} = k[	ext{A}]^2. If $$the initial rate is $$0.011\ 	ext{M} \cdot 	ext{s}^{-1} at$$ $$[	ext{A}] = 1.0\ 	ext{M}$$, what will the rate be if $$[	ext{A}] is $$increased to $$2.0\ 	ext{M}$$?

Accepted Answer

$$0.044\ 	ext{M} \cdot 	ext{s}^{-1}$$

Kinetics: Reaction Rates and Rate Laws in General Chemistry

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