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title: "\\[ \\text{A}_2\\text{(g)} + \\text{B}_2\\text{(g)} \\rightleftharpoons 2\\,\\text{AB(g)} \\]  A reversible gas-phase reaction is represented by the equation above. In Experiment 1, a rigid \\(1.0\\text{ L}\\) container at a constant temperature of \\(500\\text{ K}\\) contains an equilibrium mixture consisting of \\(2\\) molecules of \\(\\text{A}_2\\), \\(2\\) molecules of \\(\\text{B}_2\\), and \\(4\\) molecules of \\(\\text{AB}\\), as shown in the diagram below (where each particle represents \\(0.10\\text{ mol}\\) of gas).  In Experiment 2, a second identical \\(1.0\\text{ L}\\) rigid container at the same temperature of \\(500\\text{ K}\\) is initially filled with \\(6\\) molecules of \\(\\text{A}_2\\) and \\(6\\) molecules of \\(\\text{B}_2\\) (\\(0.60\\text{ mol}\\) of each gas) and allowed to reach equilibrium.  Which of the following particulate diagrams best represents the equilibrium mixture in Experiment 2?"
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url: "https://nerd-notes.com/ubq/123905/"
date_modified: "2026-09-28T12:31:01+00:00"
---

# \[ \text{A}_2\text{(g)} + \text{B}_2\text{(g)} \rightleftharpoons 2\,\text{AB(g)} \]

A reversible gas-phase reaction is represented by the equation above. In Experiment 1, a rigid \(1.0\text{ L}\) container at a constant temperature of \(500\text{ K}\) contains an equilibrium mixture consisting of \(2\) molecules of \(\text{A}_2\), \(2\) molecules of \(\text{B}_2\), and \(4\) molecules of \(\text{AB}\), as shown in the diagram below (where each particle represents \(0.10\text{ mol}\) of gas).

In Experiment 2, a second identical \(1.0\text{ L}\) rigid container at the same temperature of \(500\text{ K}\) is initially filled with \(6\) molecules of \(\text{A}_2\) and \(6\) molecules of \(\text{B}_2\) (\(0.60\text{ mol}\) of each gas) and allowed to reach equilibrium.

Which of the following particulate diagrams best represents the equilibrium mixture in Experiment 2?

\[ \text{A}_2\text{(g)} + \text{B}_2\text{(g)} \rightleftharpoons 2\,\text{AB(g)} \]

A reversible gas-phase reaction is represented by the equation above. In Experiment 1, a rigid \(1.0\text{ L}\) container at a constant temperature of \(500\text{ K}\) contains an equilibrium mixture consisting of \(2\) molecules of \(\text{A}_2\), \(2\) molecules of \(\text{B}_2\), and \(4\) molecules of \(\text{AB}\), as shown in the diagram below (where each particle represents \(0.10\text{ mol}\) of gas).

In Experiment 2, a second identical \(1.0\text{ L}\) rigid container at the same temperature of \(500\text{ K}\) is initially filled with \(6\) molecules of \(\text{A}_2\) and \(6\) molecules of \(\text{B}_2\) (\(0.60\text{ mol}\) of each gas) and allowed to reach equilibrium.

Which of the following particulate diagrams best represents the equilibrium mixture in Experiment 2?

![A square box representing a rigid 1.0 L container. A legend at the top displays: open white circle = A atom, solid black circle = B atom; a pair of two touching open white circles = A2; a pair of two touching solid black circles = B2; a pair of one open white circle touching one solid black circle = AB. Inside the square container, there are exactly 2 A2 molecules, exactly 2 B2 molecules, and exactly 4 AB molecules. The 8 total molecules are dispersed evenly throughout the interior space. No other particles, labels, text, or annotations appear.](https://nerd-notes.com/wp-content/uploads/ubq-frq-generated/stem-fig-1-1790598659-djS2qS.jpg)

- **A.** Diagram A
- **B.** Diagram B
- **C.** Diagram C
- **D.** Diagram D

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/123905/*