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title: "At \\(400\\text{ K}\\), the equilibrium constant \\(K_c\\) for the reaction represented below is \\(5.0\\).  \\[\\text{CO(g)} + \\text{Cl}_2\\text{(g)} \\rightleftharpoons \\text{COCl}_2\\text{(g)}\\]  A student injects \\(0.20\\text{ mol}\\) of \\(\\text{CO(g)}\\), \\(0.20\\text{ mol}\\) of \\(\\text{Cl}_2\\text{(g)}\\), and \\(0.40\\text{ mol}\\) of \\(\\text{COCl}_2\\text{(g)}\\) into an evacuated, rigid \\(1.0\\text{ L}\\) container at \\(400\\text{ K}\\). Which of the following correctly predicts the direction the reaction will proceed to reach equilibrium, and provides the correct justification?"
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url: "https://nerd-notes.com/ubq/119991/"
date_modified: "2026-08-21T08:31:39+00:00"
---

# At \(400\text{ K}\), the equilibrium constant \(K_c\) for the reaction represented below is \(5.0\).

\[\text{CO(g)} + \text{Cl}_2\text{(g)} \rightleftharpoons \text{COCl}_2\text{(g)}\]

A student injects \(0.20\text{ mol}\) of \(\text{CO(g)}\), \(0.20\text{ mol}\) of \(\text{Cl}_2\text{(g)}\), and \(0.40\text{ mol}\) of \(\text{COCl}_2\text{(g)}\) into an evacuated, rigid \(1.0\text{ L}\) container at \(400\text{ K}\). Which of the following correctly predicts the direction the reaction will proceed to reach equilibrium, and provides the correct justification?

At \(400\text{ K}\), the equilibrium constant \(K_c\) for the reaction represented below is \(5.0\).

\[\text{CO(g)} + \text{Cl}_2\text{(g)} \rightleftharpoons \text{COCl}_2\text{(g)}\]

A student injects \(0.20\text{ mol}\) of \(\text{CO(g)}\), \(0.20\text{ mol}\) of \(\text{Cl}_2\text{(g)}\), and \(0.40\text{ mol}\) of \(\text{COCl}_2\text{(g)}\) into an evacuated, rigid \(1.0\text{ L}\) container at \(400\text{ K}\). Which of the following correctly predicts the direction the reaction will proceed to reach equilibrium, and provides the correct justification?

- **A.** The reaction will shift toward the reactants because \(Q_c > K_c\).
- **B.** The reaction will shift toward the products because \(Q_c < K_c\).
- **C.** The reaction will shift toward the products because \(Q_c > K_c\).
- **D.** The system is already at equilibrium because \(Q_c = K_c\).

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/119991/*