---
title: "A rigid, sealed vessel contains a sample of pure \\(\\text{I}_2\\text{(g)}\\) at an initial temperature of \\(400\\text{ K}\\) and an initial pressure of \\(1.20\\text{ atm}\\). The vessel is heated to a final temperature of \\(800\\text{ K}\\). At this higher temperature, exactly \\(50.0\\%\\) of the initial \\(\\text{I}_2\\text{(g)}\\) molecules dissociate into individual iodine atoms according to the following reaction:  \\[\\text{I}_2\\text{(g)} \\rightleftharpoons 2\\text{I(g)}\\]  Assuming ideal gas behavior, what is the final total pressure inside the vessel?"
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url: "https://nerd-notes.com/ubq/123660/"
date_modified: "2026-09-28T12:01:55+00:00"
---

# A rigid, sealed vessel contains a sample of pure \(\text{I}_2\text{(g)}\) at an initial temperature of \(400\text{ K}\) and an initial pressure of \(1.20\text{ atm}\). The vessel is heated to a final temperature of \(800\text{ K}\). At this higher temperature, exactly \(50.0\%\) of the initial \(\text{I}_2\text{(g)}\) molecules dissociate into individual iodine atoms according to the following reaction:

\[\text{I}_2\text{(g)} \rightleftharpoons 2\text{I(g)}\]

Assuming ideal gas behavior, what is the final total pressure inside the vessel?

A rigid, sealed vessel contains a sample of pure \(\text{I}_2\text{(g)}\) at an initial temperature of \(400\text{ K}\) and an initial pressure of \(1.20\text{ atm}\). The vessel is heated to a final temperature of \(800\text{ K}\). At this higher temperature, exactly \(50.0\%\) of the initial \(\text{I}_2\text{(g)}\) molecules dissociate into individual iodine atoms according to the following reaction:

\[\text{I}_2\text{(g)} \rightleftharpoons 2\text{I(g)}\]

Assuming ideal gas behavior, what is the final total pressure inside the vessel?

- **A.** \(1.80\text{ atm}\)
- **B.** \(2.40\text{ atm}\)
- **C.** \(3.60\text{ atm}\)
- **D.** \(4.80\text{ atm}\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/123660/*