---
title: "The combustion of carbon monoxide is represented by the thermochemical equation below:  \\[ 2\\,\\text{CO}(g) + \\text{O}_2(g) \\rightarrow 2\\,\\text{CO}_2(g) \\quad \\Delta H^\\circ = -560\\text{ kJ/mol}_{\\text{rxn}} \\]  The equation is rewritten by multiplying all stoichiometric coefficients by a factor of \\(2\\):  \\[ 4\\,\\text{CO}(g) + 2\\,\\text{O}_2(g) \\rightarrow 4\\,\\text{CO}_2(g) \\]  If a \\(0.50\\text{ mol}\\) sample of \\(\\text{CO}(g)\\) reacts completely with excess \\(\\text{O}_2(g)\\), which of the following correctly gives the value of \\(\\Delta H^\\circ\\) for the rewritten equation and the quantity of heat released by the reaction of the sample?"
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url: "https://nerd-notes.com/ubq/123828/"
date_modified: "2026-09-28T12:30:28+00:00"
---

# The combustion of carbon monoxide is represented by the thermochemical equation below:

\[ 2\,\text{CO}(g) + \text{O}_2(g) \rightarrow 2\,\text{CO}_2(g) \quad \Delta H^\circ = -560\text{ kJ/mol}_{\text{rxn}} \]

The equation is rewritten by multiplying all stoichiometric coefficients by a factor of \(2\):

\[ 4\,\text{CO}(g) + 2\,\text{O}_2(g) \rightarrow 4\,\text{CO}_2(g) \]

If a \(0.50\text{ mol}\) sample of \(\text{CO}(g)\) reacts completely with excess \(\text{O}_2(g)\), which of the following correctly gives the value of \(\Delta H^\circ\) for the rewritten equation and the quantity of heat released by the reaction of the sample?

The combustion of carbon monoxide is represented by the thermochemical equation below:

\[ 2\,\text{CO}(g) + \text{O}_2(g) \rightarrow 2\,\text{CO}_2(g) \quad \Delta H^\circ = -560\text{ kJ/mol}_{\text{rxn}} \]

The equation is rewritten by multiplying all stoichiometric coefficients by a factor of \(2\):

\[ 4\,\text{CO}(g) + 2\,\text{O}_2(g) \rightarrow 4\,\text{CO}_2(g) \]

If a \(0.50\text{ mol}\) sample of \(\text{CO}(g)\) reacts completely with excess \(\text{O}_2(g)\), which of the following correctly gives the value of \(\Delta H^\circ\) for the rewritten equation and the quantity of heat released by the reaction of the sample?

- **A.** \(\Delta H^\circ = -560\text{ kJ/mol}_{\text{rxn}}\), and the heat released is \(70\text{ kJ}\)
- **B.** \(\Delta H^\circ = -560\text{ kJ/mol}_{\text{rxn}}\), and the heat released is \(140\text{ kJ}\)
- **C.** \(\Delta H^\circ = -1120\text{ kJ/mol}_{\text{rxn}}\), and the heat released is \(140\text{ kJ}\)
- **D.** \(\Delta H^\circ = -1120\text{ kJ/mol}_{\text{rxn}}\), and the heat released is \(280\text{ kJ}\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/123828/*