---
title: "A rigid \\(2.0\\text{ L}\\) container holds \\(0.10\\text{ mol}\\) of \\(\\text{He(g)}\\) at a constant temperature, exerting a pressure of \\(1.2\\text{ atm}\\). A sample of \\(0.20\\text{ mol}\\) of \\(\\text{Ar(g)}\\) is then injected into the container at the same temperature. Assuming ideal behavior, what is the total pressure inside the container after the \\(\\text{Ar(g)}\\) is added?"
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url: "https://nerd-notes.com/ubq/121374/"
date_modified: "2026-08-23T05:01:57+00:00"
---

# A rigid \(2.0\text{ L}\) container holds \(0.10\text{ mol}\) of \(\text{He(g)}\) at a constant temperature, exerting a pressure of \(1.2\text{ atm}\). A sample of \(0.20\text{ mol}\) of \(\text{Ar(g)}\) is then injected into the container at the same temperature. Assuming ideal behavior, what is the total pressure inside the container after the \(\text{Ar(g)}\) is added?

A rigid \(2.0\text{ L}\) container holds \(0.10\text{ mol}\) of \(\text{He(g)}\) at a constant temperature, exerting a pressure of \(1.2\text{ atm}\). A sample of \(0.20\text{ mol}\) of \(\text{Ar(g)}\) is then injected into the container at the same temperature. Assuming ideal behavior, what is the total pressure inside the container after the \(\text{Ar(g)}\) is added?

- **A.** \(1.2\text{ atm}\)
- **B.** \(1.8\text{ atm}\)
- **C.** \(2.4\text{ atm}\)
- **D.** \(3.6\text{ atm}\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/121374/*