---
title: "A rigid container at \\(500\\text{ K}\\) is charged with \\(\\text{PCl}_3\\text{(g)}\\), \\(\\text{Cl}_2\\text{(g)}\\), and \\(\\text{PCl}_5\\text{(g)}\\) such that the initial partial pressures are \\(P_{\\text{PCl}_3} = 0.50\\text{ atm}\\), \\(P_{\\text{Cl}_2} = 0.20\\text{ atm}\\), and \\(P_{\\text{PCl}_5} = 0.40\\text{ atm}\\). The reversible reaction is represented by the following equation:  \\[\\text{PCl}_3\\text{(g)} + \\text{Cl}_2\\text{(g)} \\rightleftharpoons \\text{PCl}_5\\text{(g)} \\quad K_p = 2.0 \\text{ at } 500\\text{ K}\\]  Which of the following correctly predicts the direction the reaction will proceed to establish equilibrium and provides the appropriate comparison between \\(Q_p\\) and \\(K_p\\)?"
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url: "https://nerd-notes.com/ubq/123769/"
date_modified: "2026-09-28T12:30:14+00:00"
---

# A rigid container at \(500\text{ K}\) is charged with \(\text{PCl}_3\text{(g)}\), \(\text{Cl}_2\text{(g)}\), and \(\text{PCl}_5\text{(g)}\) such that the initial partial pressures are \(P_{\text{PCl}_3} = 0.50\text{ atm}\), \(P_{\text{Cl}_2} = 0.20\text{ atm}\), and \(P_{\text{PCl}_5} = 0.40\text{ atm}\). The reversible reaction is represented by the following equation:

\[\text{PCl}_3\text{(g)} + \text{Cl}_2\text{(g)} \rightleftharpoons \text{PCl}_5\text{(g)} \quad K_p = 2.0 \text{ at } 500\text{ K}\]

Which of the following correctly predicts the direction the reaction will proceed to establish equilibrium and provides the appropriate comparison between \(Q_p\) and \(K_p\)?

A rigid container at \(500\text{ K}\) is charged with \(\text{PCl}_3\text{(g)}\), \(\text{Cl}_2\text{(g)}\), and \(\text{PCl}_5\text{(g)}\) such that the initial partial pressures are \(P_{\text{PCl}_3} = 0.50\text{ atm}\), \(P_{\text{Cl}_2} = 0.20\text{ atm}\), and \(P_{\text{PCl}_5} = 0.40\text{ atm}\). The reversible reaction is represented by the following equation:

\[\text{PCl}_3\text{(g)} + \text{Cl}_2\text{(g)} \rightleftharpoons \text{PCl}_5\text{(g)} \quad K_p = 2.0 \text{ at } 500\text{ K}\]

Which of the following correctly predicts the direction the reaction will proceed to establish equilibrium and provides the appropriate comparison between \(Q_p\) and \(K_p\)?

- **A.** The reaction proceeds toward the products because \(Q_p = 0.25\), which is less than \(K_p\).
- **B.** The reaction proceeds toward the reactants because \(Q_p = 4.0\), which is greater than \(K_p\).
- **C.** The reaction proceeds toward the products because \(Q_p = 4.0\), which is greater than \(K_p\).
- **D.** The reaction proceeds toward the reactants because \(Q_p = 0.25\), which is less than \(K_p\).

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/123769/*