---
title: "At \\(298\\text{ K}\\), nitrogen gas and oxygen gas react to form nitrogen monoxide according to the following equation:  \\[\\text{N}_2\\text{(g)} + \\text{O}_2\\text{(g)} \\rightleftharpoons 2\\,\\text{NO(g)} \\quad K_c = 1.0 \\times 10^{-30}\\]  An equimolar mixture of \\(\\text{N}_2\\text{(g)}\\) and \\(\\text{O}_2\\text{(g)}\\) is sealed in a rigid container at \\(298\\text{ K}\\) and allowed to reach equilibrium. Which of the following statements best describes the composition of the mixture at equilibrium, and provides the correct justification?"
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url: "https://nerd-notes.com/ubq/119962/"
date_modified: "2026-08-21T08:31:10+00:00"
---

# At \(298\text{ K}\), nitrogen gas and oxygen gas react to form nitrogen monoxide according to the following equation:

\[\text{N}_2\text{(g)} + \text{O}_2\text{(g)} \rightleftharpoons 2\,\text{NO(g)} \quad K_c = 1.0 \times 10^{-30}\]

An equimolar mixture of \(\text{N}_2\text{(g)}\) and \(\text{O}_2\text{(g)}\) is sealed in a rigid container at \(298\text{ K}\) and allowed to reach equilibrium. Which of the following statements best describes the composition of the mixture at equilibrium, and provides the correct justification?

At \(298\text{ K}\), nitrogen gas and oxygen gas react to form nitrogen monoxide according to the following equation:

\[\text{N}_2\text{(g)} + \text{O}_2\text{(g)} \rightleftharpoons 2\,\text{NO(g)} \quad K_c = 1.0 \times 10^{-30}\]

An equimolar mixture of \(\text{N}_2\text{(g)}\) and \(\text{O}_2\text{(g)}\) is sealed in a rigid container at \(298\text{ K}\) and allowed to reach equilibrium. Which of the following statements best describes the composition of the mixture at equilibrium, and provides the correct justification?

- **A.** The mixture consists primarily of \(\text{NO(g)}\) because a value of \(K_c < 1\) indicates that the forward reaction proceeds nearly to completion.
- **B.** The mixture consists primarily of \(\text{NO(g)}\) because the formation of \(2\text{ mol}\) of product from \(2\text{ mol}\) of total reactants drives the reaction forward.
- **C.** The mixture consists primarily of unreacted \(\text{N}_2\text{(g)}\) and \(\text{O}_2\text{(g)}\) because a very small equilibrium constant means the rate of the forward reaction is zero.
- **D.** The mixture consists primarily of unreacted \(\text{N}_2\text{(g)}\) and \(\text{O}_2\text{(g)}\) because \(K_c \ll 1\) indicates that reactants are strongly favored over products at equilibrium.

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/119962/*