---
title: "A student investigates the kinetics of the gas-phase reaction \\(2\\text{ NO}_2(g) \\rightarrow 2\\text{ NO}(g) + \\text{O}_2(g)\\) at a constant temperature. Based on experimental data, the reaction is determined to be second order with respect to \\(\\text{NO}_2(g)\\). The student collects the data shown in the table below.  | Trial | Initial \\([\\text{NO}_2]\\) (M) | Initial Rate of Consumption of \\(\\text{NO}_2\\) (M/s) | |—|—|—| | 1 | 0.20 | \\(1.2 \\times 10^{-3}\\) | | 2 | 0.40 | ? |  Which of the following best predicts the initial rate of consumption of \\(\\text{NO}_2(g)\\) in Trial 2 and provides the correct justification?"
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url: "https://nerd-notes.com/ubq/119299/"
date_modified: "2026-08-19T12:39:42+00:00"
---

# A student investigates the kinetics of the gas-phase reaction \(2\text{ NO}_2(g) \rightarrow 2\text{ NO}(g) + \text{O}_2(g)\) at a constant temperature. Based on experimental data, the reaction is determined to be second order with respect to \(\text{NO}_2(g)\). The student collects the data shown in the table below.

| Trial | Initial \([\text{NO}_2]\) (M) | Initial Rate of Consumption of \(\text{NO}_2\) (M/s) |
|—|—|—|
| 1 | 0.20 | \(1.2 \times 10^{-3}\) |
| 2 | 0.40 | ? |

Which of the following best predicts the initial rate of consumption of \(\text{NO}_2(g)\) in Trial 2 and provides the correct justification?

A student investigates the kinetics of the gas-phase reaction \(2\text{ NO}_2(g) \rightarrow 2\text{ NO}(g) + \text{O}_2(g)\) at a constant temperature. Based on experimental data, the reaction is determined to be second order with respect to \(\text{NO}_2(g)\). The student collects the data shown in the table below.

| Trial | Initial \([\text{NO}_2]\) (M) | Initial Rate of Consumption of \(\text{NO}_2\) (M/s) |
|---|---|---|
| 1 | 0.20 | \(1.2 \times 10^{-3}\) |
| 2 | 0.40 | ? |

Which of the following best predicts the initial rate of consumption of \(\text{NO}_2(g)\) in Trial 2 and provides the correct justification?

- **A.** The initial rate will be \(4.8 \times 10^{-3}\text{ M/s}\) because doubling the concentration of a second-order reactant increases the reaction rate by a factor of \(2^2\).
- **B.** The initial rate will be \(4.8 \times 10^{-3}\text{ M/s}\) because two moles of \(\text{NO}_2(g)\) react for every one mole of \(\text{O}_2(g)\) produced.
- **C.** The initial rate will be \(2.4 \times 10^{-3}\text{ M/s}\) because the rate of a reaction is directly proportional to the reactant concentration.
- **D.** The initial rate will be \(2.4 \times 10^{-3}\text{ M/s}\) because the stoichiometric coefficient of \(\text{NO}_2(g)\) in the balanced chemical equation is 2.

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/119299/*