---
title: "The standard molar entropy, \\(S^\\circ\\), of a pure substance depends on its state of matter, molecular complexity, and the number of available microstates. A student is provided with the following four substances at \\(298\\text{ K}\\) and \\(1\\text{ atm}\\):  \\(\\text{CH}_3\\text{OH(l)}\\), \\(\\text{CH}_4\\text{(g)}\\), \\(\\text{C}_2\\text{H}_6\\text{(g)}\\), and \\(\\text{C}_3\\text{H}_8\\text{(g)}\\)  Which of the following correctly ranks the substances in order of increasing standard molar entropy, \\(S^\\circ\\), at \\(298\\text{ K}\\)?"
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url: "https://nerd-notes.com/ubq/120330/"
date_modified: "2026-08-23T04:23:10+00:00"
---

# The standard molar entropy, \(S^\circ\), of a pure substance depends on its state of matter, molecular complexity, and the number of available microstates. A student is provided with the following four substances at \(298\text{ K}\) and \(1\text{ atm}\):

\(\text{CH}_3\text{OH(l)}\), \(\text{CH}_4\text{(g)}\), \(\text{C}_2\text{H}_6\text{(g)}\), and \(\text{C}_3\text{H}_8\text{(g)}\)

Which of the following correctly ranks the substances in order of increasing standard molar entropy, \(S^\circ\), at \(298\text{ K}\)?

The standard molar entropy, \(S^\circ\), of a pure substance depends on its state of matter, molecular complexity, and the number of available microstates. A student is provided with the following four substances at \(298\text{ K}\) and \(1\text{ atm}\):

\(\text{CH}_3\text{OH(l)}\), \(\text{CH}_4\text{(g)}\), \(\text{C}_2\text{H}_6\text{(g)}\), and \(\text{C}_3\text{H}_8\text{(g)}\)

Which of the following correctly ranks the substances in order of increasing standard molar entropy, \(S^\circ\), at \(298\text{ K}\)?

- **A.** \(\text{CH}_4\text{(g)} < \text{C}_2\text{H}_6\text{(g)} < \text{CH}_3\text{OH(l)} < \text{C}_3\text{H}_8\text{(g)}\)
- **B.** \(\text{CH}_4\text{(g)} < \text{CH}_3\text{OH(l)} < \text{C}_2\text{H}_6\text{(g)} < \text{C}_3\text{H}_8\text{(g)}\)
- **C.** \(\text{CH}_3\text{OH(l)} < \text{C}_3\text{H}_8\text{(g)} < \text{C}_2\text{H}_6\text{(g)} < \text{CH}_4\text{(g)}\)
- **D.** \(\text{CH}_3\text{OH(l)} < \text{CH}_4\text{(g)} < \text{C}_2\text{H}_6\text{(g)} < \text{C}_3\text{H}_8\text{(g)}\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/120330/*