---
title: "Methanol is synthesized industrially according to the following equation: \\[ \\text{CO}(g) + 2\\,\\text{H}_2(g) \\rightarrow \\text{CH}_3\\text{OH}(g) \\quad \\Delta H^\\circ_{rxn} = -90.0\\text{ kJ/mol}_{rxn} \\] The standard molar entropies of the substances involved in the reaction are provided in the table below.  | Substance | \\(S^\\circ\\ (\\text{J}/(\\text{mol}\\cdot\\text{K}))\\) | | :— | :— | | \\(\\text{CO}(g)\\) | \\(200\\) | | \\(\\text{H}_2(g)\\) | \\(130\\) | | \\(\\text{CH}_3\\text{OH}(g)\\) | \\(240\\) |  Assuming that \\(\\Delta H^\\circ\\) and \\(\\Delta S^\\circ\\) are constant over the temperature range, what is the value of \\(\\Delta G^\\circ_{rxn}\\) at \\(500\\text{ K}\\)?"
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url: "https://nerd-notes.com/ubq/120354/"
date_modified: "2026-08-23T04:23:21+00:00"
---

# Methanol is synthesized industrially according to the following equation:
\[ \text{CO}(g) + 2\,\text{H}_2(g) \rightarrow \text{CH}_3\text{OH}(g) \quad \Delta H^\circ_{rxn} = -90.0\text{ kJ/mol}_{rxn} \]
The standard molar entropies of the substances involved in the reaction are provided in the table below.

| Substance | \(S^\circ\ (\text{J}/(\text{mol}\cdot\text{K}))\) |
| :— | :— |
| \(\text{CO}(g)\) | \(200\) |
| \(\text{H}_2(g)\) | \(130\) |
| \(\text{CH}_3\text{OH}(g)\) | \(240\) |

Assuming that \(\Delta H^\circ\) and \(\Delta S^\circ\) are constant over the temperature range, what is the value of \(\Delta G^\circ_{rxn}\) at \(500\text{ K}\)?

Methanol is synthesized industrially according to the following equation:
\[ \text{CO}(g) + 2\,\text{H}_2(g) \rightarrow \text{CH}_3\text{OH}(g) \quad \Delta H^\circ_{rxn} = -90.0\text{ kJ/mol}_{rxn} \]
The standard molar entropies of the substances involved in the reaction are provided in the table below.

| Substance | \(S^\circ\ (\text{J}/(\text{mol}\cdot\text{K}))\) |
| :--- | :--- |
| \(\text{CO}(g)\) | \(200\) |
| \(\text{H}_2(g)\) | \(130\) |
| \(\text{CH}_3\text{OH}(g)\) | \(240\) |

Assuming that \(\Delta H^\circ\) and \(\Delta S^\circ\) are constant over the temperature range, what is the value of \(\Delta G^\circ_{rxn}\) at \(500\text{ K}\)?

- **A.** \(-200.0\text{ kJ/mol}_{rxn}\)
- **B.** \(-45.0\text{ kJ/mol}_{rxn}\)
- **C.** \(+20.0\text{ kJ/mol}_{rxn}\)
- **D.** \(+200.0\text{ kJ/mol}_{rxn}\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/120354/*