---
title: "A gaseous reaction mixture containing \\(\\text{N}_2\\text{O}_4\\text{(g)}\\) and \\(\\text{NO}_2\\text{(g)}\\) is at equilibrium inside a cylinder fitted with a movable piston at a constant temperature, as represented by the equation \\(\\text{N}_2\\text{O}_4\\text{(g)} \\rightleftharpoons 2\\text{NO}_2\\text{(g)}\\). The piston is pushed inward to decrease the volume of the container to half its initial volume. Which of the following best predicts the response of the system to re-establish equilibrium and gives the correct reasoning?"
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url: "https://nerd-notes.com/ubq/119240/"
date_modified: "2026-08-19T12:39:30+00:00"
---

# A gaseous reaction mixture containing \(\text{N}_2\text{O}_4\text{(g)}\) and \(\text{NO}_2\text{(g)}\) is at equilibrium inside a cylinder fitted with a movable piston at a constant temperature, as represented by the equation \(\text{N}_2\text{O}_4\text{(g)} \rightleftharpoons 2\text{NO}_2\text{(g)}\). The piston is pushed inward to decrease the volume of the container to half its initial volume. Which of the following best predicts the response of the system to re-establish equilibrium and gives the correct reasoning?

A gaseous reaction mixture containing \(\text{N}_2\text{O}_4\text{(g)}\) and \(\text{NO}_2\text{(g)}\) is at equilibrium inside a cylinder fitted with a movable piston at a constant temperature, as represented by the equation \(\text{N}_2\text{O}_4\text{(g)} \rightleftharpoons 2\text{NO}_2\text{(g)}\). The piston is pushed inward to decrease the volume of the container to half its initial volume. Which of the following best predicts the response of the system to re-establish equilibrium and gives the correct reasoning?

- **A.** The system shifts toward the products because decreasing the volume favors the side with a greater number of moles of gas.
- **B.** The system shifts toward the products because the value of the equilibrium constant increases when total pressure increases.
- **C.** The system shifts toward the reactants because decreasing the volume increases the total pressure, favoring the side with fewer moles of gas.
- **D.** The system shifts toward the reactants because the value of the equilibrium constant decreases when total pressure increases.

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/119240/*