---
title: "A student investigates a treatment process for chromium-containing rinse water. The solution is acidified, and chromium(VI), present as \\(\\text{Cr}_2\\text{O}_7^{2-}\\text{(aq)}\\), is reduced to \\(\\text{Cr}^{3+}\\text{(aq)}\\).  Which equation represents the correctly balanced reduction half-reaction for \\(\\text{Cr}_2\\text{O}_7^{2-}\\text{(aq)}\\) in acidic aqueous solution?"
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url: "https://nerd-notes.com/ubq/119306/"
date_modified: "2026-08-19T12:39:44+00:00"
---

# A student investigates a treatment process for chromium-containing rinse water. The solution is acidified, and chromium(VI), present as \(\text{Cr}_2\text{O}_7^{2-}\text{(aq)}\), is reduced to \(\text{Cr}^{3+}\text{(aq)}\).

Which equation represents the correctly balanced reduction half-reaction for \(\text{Cr}_2\text{O}_7^{2-}\text{(aq)}\) in acidic aqueous solution?

A student investigates a treatment process for chromium-containing rinse water. The solution is acidified, and chromium(VI), present as \(\text{Cr}_2\text{O}_7^{2-}\text{(aq)}\), is reduced to \(\text{Cr}^{3+}\text{(aq)}\).

Which equation represents the correctly balanced reduction half-reaction for \(\text{Cr}_2\text{O}_7^{2-}\text{(aq)}\) in acidic aqueous solution?

- **A.** \(\text{Cr}_2\text{O}_7^{2-}\text{(aq)} + 14\text{H}^+\text{(aq)} + 3e^- \rightarrow 2\text{Cr}^{3+}\text{(aq)} + 7\text{H}_2\text{O(l)}\)
- **B.** \(\text{Cr}_2\text{O}_7^{2-}\text{(aq)} + 14\text{H}^+\text{(aq)} + 6e^- \rightarrow 2\text{Cr}^{3+}\text{(aq)} + 7\text{H}_2\text{O(l)}\)
- **C.** \(\text{Cr}_2\text{O}_7^{2-}\text{(aq)} + 7\text{H}_2\text{O(l)} + 6e^- \rightarrow 2\text{Cr}^{3+}\text{(aq)} + 14\text{OH}^-\text{(aq)}\)
- **D.** \(2\text{Cr}^{3+}\text{(aq)} + 7\text{H}_2\text{O(l)} \rightarrow \text{Cr}_2\text{O}_7^{2-}\text{(aq)} + 14\text{H}^+\text{(aq)} + 6e^-\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/119306/*