---
title: "A mixture of methane gas, \\(\\text{CH}_4\\text{(g)}\\), and oxygen gas, \\(\\text{O}_2\\text{(g)}\\), is placed in a rigid closed vessel as represented in the diagram.  \\[ \\text{CH}_4\\text{(g)} + 2\\text{ O}_2\\text{(g)} \\rightarrow \\text{CO}_2\\text{(g)} + 2\\text{ H}_2\\text{O(g)} \\]  The mixture is ignited and the reaction proceeds to completion. Which of the following particulate diagrams best represents the contents of the vessel after the reaction is complete?"
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url: "https://nerd-notes.com/ubq/119833/"
date_modified: "2026-08-21T08:12:36+00:00"
---

# A mixture of methane gas, \(\text{CH}_4\text{(g)}\), and oxygen gas, \(\text{O}_2\text{(g)}\), is placed in a rigid closed vessel as represented in the diagram.

\[ \text{CH}_4\text{(g)} + 2\text{ O}_2\text{(g)} \rightarrow \text{CO}_2\text{(g)} + 2\text{ H}_2\text{O(g)} \]

The mixture is ignited and the reaction proceeds to completion. Which of the following particulate diagrams best represents the contents of the vessel after the reaction is complete?

A mixture of methane gas, \(\text{CH}_4\text{(g)}\), and oxygen gas, \(\text{O}_2\text{(g)}\), is placed in a rigid closed vessel as represented in the diagram.

\[ \text{CH}_4\text{(g)} + 2\text{ O}_2\text{(g)} \rightarrow \text{CO}_2\text{(g)} + 2\text{ H}_2\text{O(g)} \]

The mixture is ignited and the reaction proceeds to completion. Which of the following particulate diagrams best represents the contents of the vessel after the reaction is complete?

![A schematic diagram showing a cross-section of a sealed reaction container alongside a legend. The legend maps three atomic symbols: a large filled black circle represents \(\text{C}\), a small open white circle represents \(\text{H}\), and a medium gray-filled circle represents \(\text{O}\). The legend defines a \(\text{CH}_4\) molecule as 1 central large black circle surrounded by 4 touching small open white circles, and an \(\text{O}_2\) molecule as 2 touching medium gray circles. Inside the rectangular container boundary, exactly 3 \(\text{CH}_4\) molecules and exactly 4 \(\text{O}_2\) molecules are dispersed evenly without touching one another. No other particles, labels, text, or annotations appear.](https://nerd-notes.com/wp-content/uploads/ubq-frq-generated/stem-fig-1-1787299955-uXVbAg.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/119833/*