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title: "The oxidation of nitric oxide to nitrogen dioxide is represented by the overall balanced equation below.  \\[ 2\\,\\text{NO}(g) + \\text{O}_2(g) \\rightarrow 2\\,\\text{NO}_2(g) \\]  A proposed two-step mechanism for the reaction consists of a fast reversible first step followed by a slow second step:  \\[ \\text{Step 1: } 2\\,\\text{NO}(g) \\underset{k_{-1}}{\\overset{k_1}{\\rightleftharpoons}} \\text{N}_2\\text{O}_2(g) \\quad (\\text{fast pre-equilibrium}) \\] \\[ \\text{Step 2: } \\text{N}_2\\text{O}_2(g) + \\text{O}_2(g) \\xrightarrow{k_2} 2\\,\\text{NO}_2(g) \\quad (\\text{slow}) \\]  Which of the following rate law expressions is consistent with this proposed mechanism?"
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url: "https://nerd-notes.com/ubq/119869/"
date_modified: "2026-08-21T08:16:40+00:00"
---

# The oxidation of nitric oxide to nitrogen dioxide is represented by the overall balanced equation below.

\[ 2\,\text{NO}(g) + \text{O}_2(g) \rightarrow 2\,\text{NO}_2(g) \]

A proposed two-step mechanism for the reaction consists of a fast reversible first step followed by a slow second step:

\[ \text{Step 1: } 2\,\text{NO}(g) \underset{k_{-1}}{\overset{k_1}{\rightleftharpoons}} \text{N}_2\text{O}_2(g) \quad (\text{fast pre-equilibrium}) \]
\[ \text{Step 2: } \text{N}_2\text{O}_2(g) + \text{O}_2(g) \xrightarrow{k_2} 2\,\text{NO}_2(g) \quad (\text{slow}) \]

Which of the following rate law expressions is consistent with this proposed mechanism?

The oxidation of nitric oxide to nitrogen dioxide is represented by the overall balanced equation below.

\[ 2\,\text{NO}(g) + \text{O}_2(g) \rightarrow 2\,\text{NO}_2(g) \]

A proposed two-step mechanism for the reaction consists of a fast reversible first step followed by a slow second step:

\[ \text{Step 1: } 2\,\text{NO}(g) \underset{k_{-1}}{\overset{k_1}{\rightleftharpoons}} \text{N}_2\text{O}_2(g) \quad (\text{fast pre-equilibrium}) \]
\[ \text{Step 2: } \text{N}_2\text{O}_2(g) + \text{O}_2(g) \xrightarrow{k_2} 2\,\text{NO}_2(g) \quad (\text{slow}) \]

Which of the following rate law expressions is consistent with this proposed mechanism?

- **A.** \(\text{Rate} = \dfrac{k_1 k_2}{k_{-1}} [\text{NO}][\text{O}_2]\)
- **B.** \(\text{Rate} = \dfrac{k_1 k_2}{k_{-1}} [\text{NO}]^2 [\text{O}_2]\)
- **C.** \(\text{Rate} = \dfrac{k_{-1} k_2}{k_1} [\text{NO}]^2 [\text{O}_2]\)
- **D.** \(\text{Rate} = k_1 k_2 [\text{NO}]^2 [\text{O}_2]\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/119869/*