---
title: "A sample of \\(\\text{PCl}_5\\text{(g)}\\) is placed in a rigid, sealed container and heated to a constant temperature. The system reaches equilibrium according to the following equation:  \\[ \\text{PCl}_5\\text{(g)} \\rightleftharpoons \\text{PCl}_3\\text{(g)} + \\text{Cl}_2\\text{(g)} \\]  At equilibrium, the molar concentrations of the gases are measured to be \\([\\text{PCl}_5] = 0.40 \\text{ M}\\), \\([\\text{PCl}_3] = 0.20 \\text{ M}\\), and \\([\\text{Cl}_2] = 0.30 \\text{ M}\\). What is the value of the equilibrium constant, \\(K_c\\), for the reaction at this temperature?"
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url: "https://nerd-notes.com/ubq/120285/"
date_modified: "2026-08-23T04:04:16+00:00"
---

# A sample of \(\text{PCl}_5\text{(g)}\) is placed in a rigid, sealed container and heated to a constant temperature. The system reaches equilibrium according to the following equation:

\[ \text{PCl}_5\text{(g)} \rightleftharpoons \text{PCl}_3\text{(g)} + \text{Cl}_2\text{(g)} \]

At equilibrium, the molar concentrations of the gases are measured to be \([\text{PCl}_5] = 0.40 \text{ M}\), \([\text{PCl}_3] = 0.20 \text{ M}\), and \([\text{Cl}_2] = 0.30 \text{ M}\). What is the value of the equilibrium constant, \(K_c\), for the reaction at this temperature?

A sample of \(\text{PCl}_5\text{(g)}\) is placed in a rigid, sealed container and heated to a constant temperature. The system reaches equilibrium according to the following equation:

\[ \text{PCl}_5\text{(g)} \rightleftharpoons \text{PCl}_3\text{(g)} + \text{Cl}_2\text{(g)} \]

At equilibrium, the molar concentrations of the gases are measured to be \([\text{PCl}_5] = 0.40 \text{ M}\), \([\text{PCl}_3] = 0.20 \text{ M}\), and \([\text{Cl}_2] = 0.30 \text{ M}\). What is the value of the equilibrium constant, \(K_c\), for the reaction at this temperature?

- **A.** \(0.060\)
- **B.** \(0.10\)
- **C.** \(0.15\)
- **D.** \(6.7\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/120285/*