---
title: "An equimolar mixture of \\(\\text{CH}_4\\text{(g)}\\) (molar mass \\(16\\text{ g/mol}\\)) and \\(\\text{SO}_2\\text{(g)}\\) (molar mass \\(64\\text{ g/mol}\\)) is placed in a sealed container at \\(298\\text{ K}\\). A microscopic pinhole is opened in the container wall, allowing gas molecules to effuse into an adjacent evacuated chamber. Which of the following best predicts the composition of the gas mixture collected in the evacuated chamber during the initial stages of effusion, and provides the correct justification?"
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url: "https://nerd-notes.com/ubq/123626/"
date_modified: "2026-09-28T12:01:49+00:00"
---

# An equimolar mixture of \(\text{CH}_4\text{(g)}\) (molar mass \(16\text{ g/mol}\)) and \(\text{SO}_2\text{(g)}\) (molar mass \(64\text{ g/mol}\)) is placed in a sealed container at \(298\text{ K}\). A microscopic pinhole is opened in the container wall, allowing gas molecules to effuse into an adjacent evacuated chamber. Which of the following best predicts the composition of the gas mixture collected in the evacuated chamber during the initial stages of effusion, and provides the correct justification?

An equimolar mixture of \(\text{CH}_4\text{(g)}\) (molar mass \(16\text{ g/mol}\)) and \(\text{SO}_2\text{(g)}\) (molar mass \(64\text{ g/mol}\)) is placed in a sealed container at \(298\text{ K}\). A microscopic pinhole is opened in the container wall, allowing gas molecules to effuse into an adjacent evacuated chamber. Which of the following best predicts the composition of the gas mixture collected in the evacuated chamber during the initial stages of effusion, and provides the correct justification?

- **A.** The effused mixture contains approximately \(4\) times as many moles of \(\text{CH}_4\text{(g)}\) as \(\text{SO}_2\text{(g)}\) because the effusion rate of a gas is inversely proportional to its molar mass.
- **B.** The effused mixture contains equal numbers of moles of \(\text{CH}_4\text{(g)}\) and \(\text{SO}_2\text{(g)}\) because both gases possess the same average kinetic energy at \(298\text{ K}\).
- **C.** The effused mixture contains approximately \(2\) times as many moles of \(\text{CH}_4\text{(g)}\) as \(\text{SO}_2\text{(g)}\) because the root-mean-square speed of \(\text{CH}_4\) molecules is \(2\) times that of \(\text{SO}_2\) molecules at \(298\text{ K}\).
- **D.** The effused mixture contains approximately \(2\) times as many moles of \(\text{SO}_2\text{(g)}\) as \(\text{CH}_4\text{(g)}\) because heavier molecules possess greater momentum to escape through the pinhole.

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