---
title: "The gas-phase decomposition of nitrogen dioxide at \\(500\\text{ K}\\) is represented by the equation below.  \\[ 2\\,\\text{NO}_2\\text{(g)} \\rightarrow 2\\,\\text{NO(g)} + \\text{O}_2\\text{(g)} \\]  The reaction is second order with respect to \\(\\text{NO}_2\\text{(g)}\\), with the rate law:  \\[ \\text{Rate} = k[\\text{NO}_2]^2 \\]  In an experiment at \\(500\\text{ K}\\), when \\([\\text{NO}_2] = 0.050\\text{ M}\\), the initial rate of the reaction is \\(2.5 \\times 10^{-4}\\text{ M}\\cdot\\text{s}^{-1}\\). What is the value of the rate constant, \\(k\\), at this temperature?"
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url: "https://nerd-notes.com/ubq/119714/"
date_modified: "2026-08-21T08:12:08+00:00"
---

# The gas-phase decomposition of nitrogen dioxide at \(500\text{ K}\) is represented by the equation below.

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

The reaction is second order with respect to \(\text{NO}_2\text{(g)}\), with the rate law:

\[ \text{Rate} = k[\text{NO}_2]^2 \]

In an experiment at \(500\text{ K}\), when \([\text{NO}_2] = 0.050\text{ M}\), the initial rate of the reaction is \(2.5 \times 10^{-4}\text{ M}\cdot\text{s}^{-1}\). What is the value of the rate constant, \(k\), at this temperature?

The gas-phase decomposition of nitrogen dioxide at \(500\text{ K}\) is represented by the equation below.

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

The reaction is second order with respect to \(\text{NO}_2\text{(g)}\), with the rate law:

\[ \text{Rate} = k[\text{NO}_2]^2 \]

In an experiment at \(500\text{ K}\), when \([\text{NO}_2] = 0.050\text{ M}\), the initial rate of the reaction is \(2.5 \times 10^{-4}\text{ M}\cdot\text{s}^{-1}\). What is the value of the rate constant, \(k\), at this temperature?

- **A.** \(0.10\text{ M}^{-1}\cdot\text{s}^{-1}\)
- **B.** \(0.20\text{ M}^{-1}\cdot\text{s}^{-1}\)
- **C.** \(1.0\text{ M}^{-1}\cdot\text{s}^{-1}\)
- **D.** \(10\text{ M}^{-1}\cdot\text{s}^{-1}\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/119714/*