---
title: "A \\(3.00\\text{ g}\\) sample of a pure organic compound containing only carbon, hydrogen, and oxygen is completely combusted in excess oxygen gas, producing \\(4.40\\text{ g}\\) of \\(\\text{CO}_2\\text{(g)}\\) and \\(1.80\\text{ g}\\) of \\(\\text{H}_2\\text{O(g)}\\). What is the percent by mass of oxygen in the original compound?"
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url: "https://nerd-notes.com/ubq/121508/"
date_modified: "2026-08-23T05:04:55+00:00"
---

# A \(3.00\text{ g}\) sample of a pure organic compound containing only carbon, hydrogen, and oxygen is completely combusted in excess oxygen gas, producing \(4.40\text{ g}\) of \(\text{CO}_2\text{(g)}\) and \(1.80\text{ g}\) of \(\text{H}_2\text{O(g)}\). What is the percent by mass of oxygen in the original compound?

A \(3.00\text{ g}\) sample of a pure organic compound containing only carbon, hydrogen, and oxygen is completely combusted in excess oxygen gas, producing \(4.40\text{ g}\) of \(\text{CO}_2\text{(g)}\) and \(1.80\text{ g}\) of \(\text{H}_2\text{O(g)}\). What is the percent by mass of oxygen in the original compound?

- **A.** \(40.0\%\)
- **B.** \(53.3\%\)
- **C.** \(56.7\%\)
- **D.** \(60.0\%\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/121508/*