---
title: "A sample of \\(\\text{COCl}_2\\text{(g)}\\) decomposes in a rigid, sealed \\(1.0\\text{ L}\\) container at a constant temperature according to the equation below.  \\[ \\text{COCl}_2\\text{(g)} \\rightleftharpoons \\text{CO(g)} + \\text{Cl}_2\\text{(g)} \\]  At equilibrium, the partial pressures of the gases are \\(P_{\\text{COCl}_2} = 0.20\\text{ atm}\\), \\(P_{\\text{CO}} = 0.40\\text{ atm}\\), and \\(P_{\\text{Cl}_2} = 0.40\\text{ atm}\\). An additional \\(0.40\\text{ atm}\\) of \\(\\text{Cl}_2\\text{(g)}\\) is injected into the container at the same temperature. Which of the following correctly gives the value of the reaction quotient, \\(Q_p\\), immediately after the addition of \\(\\text{Cl}_2\\text{(g)}\\) and predicts the direction of the net reaction as equilibrium is re-established?"
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url: "https://nerd-notes.com/ubq/119734/"
date_modified: "2026-08-21T08:12:10+00:00"
---

# A sample of \(\text{COCl}_2\text{(g)}\) decomposes in a rigid, sealed \(1.0\text{ L}\) container at a constant temperature according to the equation below.

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

At equilibrium, the partial pressures of the gases are \(P_{\text{COCl}_2} = 0.20\text{ atm}\), \(P_{\text{CO}} = 0.40\text{ atm}\), and \(P_{\text{Cl}_2} = 0.40\text{ atm}\). An additional \(0.40\text{ atm}\) of \(\text{Cl}_2\text{(g)}\) is injected into the container at the same temperature. Which of the following correctly gives the value of the reaction quotient, \(Q_p\), immediately after the addition of \(\text{Cl}_2\text{(g)}\) and predicts the direction of the net reaction as equilibrium is re-established?

A sample of \(\text{COCl}_2\text{(g)}\) decomposes in a rigid, sealed \(1.0\text{ L}\) container at a constant temperature according to the equation below.

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

At equilibrium, the partial pressures of the gases are \(P_{\text{COCl}_2} = 0.20\text{ atm}\), \(P_{\text{CO}} = 0.40\text{ atm}\), and \(P_{\text{Cl}_2} = 0.40\text{ atm}\). An additional \(0.40\text{ atm}\) of \(\text{Cl}_2\text{(g)}\) is injected into the container at the same temperature. Which of the following correctly gives the value of the reaction quotient, \(Q_p\), immediately after the addition of \(\text{Cl}_2\text{(g)}\) and predicts the direction of the net reaction as equilibrium is re-established?

- **A.** \(Q_p = 1.6\); the net reaction proceeds toward reactants because \(Q_p > K_p\).
- **B.** \(Q_p = 1.6\); the net reaction proceeds toward products because \(Q_p > K_p\).
- **C.** \(Q_p = 0.63\); the net reaction proceeds toward products because \(Q_p < K_p\).
- **D.** \(Q_p = 0.63\); the net reaction proceeds toward reactants because \(Q_p < K_p\).

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/119734/*