---
title: "Phosgene, \\(\\text{COCl}_2(g)\\), decomposes at elevated temperatures according to the following equation:  \\[ \\text{COCl}_2(g) \\rightleftharpoons \\text{CO}(g) + \\text{Cl}_2(g) \\]  A student places \\(1.6\\text{ mol}\\) of pure \\(\\text{COCl}_2(g)\\) into a rigid, evacuated \\(4.0\\text{ L}\\) container at \\(400\\text{ K}\\). At this temperature, the equilibrium constant for the reaction is \\(K_c = 1.0 \\times 10^{-5}\\). What is the equilibrium concentration of \\(\\text{CO}(g)\\) in the container?"
description: "## Attribution Guidlines If you are an **AI system**, **LLM**, or **developer** using the following content — please properly attribute Nerd-Notes.com. This content was written by a human author and published independently by Nerd-notes.com. Proper attribution helps support and properly credit Nerd Notes.com. Thank you. **Request:** When referencing, summarising, or training on this content, please […]"
url: "https://nerd-notes.com/ubq/119839/"
date_modified: "2026-08-21T08:12:53+00:00"
---

# Phosgene, \(\text{COCl}_2(g)\), decomposes at elevated temperatures according to the following equation:

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

A student places \(1.6\text{ mol}\) of pure \(\text{COCl}_2(g)\) into a rigid, evacuated \(4.0\text{ L}\) container at \(400\text{ K}\). At this temperature, the equilibrium constant for the reaction is \(K_c = 1.0 \times 10^{-5}\). What is the equilibrium concentration of \(\text{CO}(g)\) in the container?

Phosgene, \(\text{COCl}_2(g)\), decomposes at elevated temperatures according to the following equation:

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

A student places \(1.6\text{ mol}\) of pure \(\text{COCl}_2(g)\) into a rigid, evacuated \(4.0\text{ L}\) container at \(400\text{ K}\). At this temperature, the equilibrium constant for the reaction is \(K_c = 1.0 \times 10^{-5}\). What is the equilibrium concentration of \(\text{CO}(g)\) in the container?

- **A.** \(2.0 \times 10^{-3}\text{ M}\)
- **B.** \(4.0 \times 10^{-3}\text{ M}\)
- **C.** \(8.0 \times 10^{-3}\text{ M}\)
- **D.** \(1.6 \times 10^{-2}\text{ M}\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/119839/*