---
title: "Hypochlorous acid, \\(\\text{HOCl}\\), has an acid-dissociation constant \\(K_a = 2.5 \\times 10^{-8}\\) at \\(25^\\circ\\text{C}\\). A student prepares a \\(0.10\\text{ M}\\) aqueous solution of sodium hypochlorite, \\(\\text{NaOCl(aq)}\\), at \\(25^\\circ\\text{C}\\).  \\[ \\text{OCl}^-\\text{(aq)} + \\text{H}_2\\text{O(l)} \\rightleftharpoons \\text{HOCl(aq)} + \\text{OH}^-\\text{(aq)} \\]  Assuming that \\(K_w = 1.0 \\times 10^{-14}\\) at \\(25^\\circ\\text{C}\\), what is the equilibrium concentration of \\(\\text{OH}^-\\text{(aq)}\\) in the solution?"
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url: "https://nerd-notes.com/ubq/119741/"
date_modified: "2026-08-21T08:12:11+00:00"
---

# Hypochlorous acid, \(\text{HOCl}\), has an acid-dissociation constant \(K_a = 2.5 \times 10^{-8}\) at \(25^\circ\text{C}\). A student prepares a \(0.10\text{ M}\) aqueous solution of sodium hypochlorite, \(\text{NaOCl(aq)}\), at \(25^\circ\text{C}\).

\[ \text{OCl}^-\text{(aq)} + \text{H}_2\text{O(l)} \rightleftharpoons \text{HOCl(aq)} + \text{OH}^-\text{(aq)} \]

Assuming that \(K_w = 1.0 \times 10^{-14}\) at \(25^\circ\text{C}\), what is the equilibrium concentration of \(\text{OH}^-\text{(aq)}\) in the solution?

Hypochlorous acid, \(\text{HOCl}\), has an acid-dissociation constant \(K_a = 2.5 \times 10^{-8}\) at \(25^\circ\text{C}\). A student prepares a \(0.10\text{ M}\) aqueous solution of sodium hypochlorite, \(\text{NaOCl(aq)}\), at \(25^\circ\text{C}\).

\[ \text{OCl}^-\text{(aq)} + \text{H}_2\text{O(l)} \rightleftharpoons \text{HOCl(aq)} + \text{OH}^-\text{(aq)} \]

Assuming that \(K_w = 1.0 \times 10^{-14}\) at \(25^\circ\text{C}\), what is the equilibrium concentration of \(\text{OH}^-\text{(aq)}\) in the solution?

- **A.** \(5.0 \times 10^{-11}\text{ M}\)
- **B.** \(4.0 \times 10^{-8}\text{ M}\)
- **C.** \(5.0 \times 10^{-5}\text{ M}\)
- **D.** \(2.0 \times 10^{-4}\text{ M}\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/119741/*