---
title: "A rigid, sealed container holds an equimolar mixture of 	ect{CH}_4	ect{(g)}\\) (molar mass \\(16.04\\text{ g/mol}\\)) and \\(\\text{SO}_2\\text{(g)}\\) (molar mass \\(64.06\\text{ g/mol}\\)) at \\(300\\text{ K}\\). Which of the following statements correctly compares the average kinetic energy of the \\(\\text{CH}_4\\text{(g)}\\) molecules to that of the \\(\\text{SO}_2\\text{(g)}\\) molecules, and provides the correct justification?"
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url: "https://nerd-notes.com/ubq/119954/"
date_modified: "2026-08-21T08:24:27+00:00"
---

# A rigid, sealed container holds an equimolar mixture of 	ect{CH}_4	ect{(g)}\) (molar mass \(16.04\text{ g/mol}\)) and \(\text{SO}_2\text{(g)}\) (molar mass \(64.06\text{ g/mol}\)) at \(300\text{ K}\). Which of the following statements correctly compares the average kinetic energy of the \(\text{CH}_4\text{(g)}\) molecules to that of the \(\text{SO}_2\text{(g)}\) molecules, and provides the correct justification?

A rigid, sealed container holds an equimolar mixture of 	ect{CH}_4	ect{(g)}\) (molar mass \(16.04\text{ g/mol}\)) and \(\text{SO}_2\text{(g)}\) (molar mass \(64.06\text{ g/mol}\)) at \(300\text{ K}\). Which of the following statements correctly compares the average kinetic energy of the \(\text{CH}_4\text{(g)}\) molecules to that of the \(\text{SO}_2\text{(g)}\) molecules, and provides the correct justification?

- **A.** The average kinetic energy of the \(\text{CH}_4\text{(g)}\) molecules is greater than that of the \(\text{SO}_2\text{(g)}\) molecules because \(\text{CH}_4\) has a lower molar mass and moves with a higher average speed.
- **B.** The average kinetic energy of the \(\text{CH}_4\text{(g)}\) molecules is greater than that of the \(\text{SO}_2\text{(g)}\) molecules because \(\text{CH}_4\) experiences weaker London dispersion forces, allowing more kinetic energy to be conserved during collisions.
- **C.** The average kinetic energy of the \(\text{CH}_4\text{(g)}\) molecules is equal to that of the \(\text{SO}_2\text{(g)}\) molecules because both gases contain an equal number of moles and exert the same partial pressure.
- **D.** The average kinetic energy of the \(\text{CH}_4\text{(g)}\) molecules is equal to that of the \(\text{SO}_2\text{(g)}\) molecules because the average kinetic energy of any gas depends only on absolute temperature, which is identical for both gases.

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/119954/*