---
title: "A student prepares a \\(0.20\\text{ M}\\) aqueous solution of a weak monoprotic acid, \\(\\text{HA}\\), with an acid-dissociation constant \\(K_a = 2.0 \\times 10^{-5}\\) at \\(25\\ ^\\circ\\text{C}\\). The ionization reaction is represented by the equation below.  \\[\\text{HA(aq)} + \\text{H}_2\\text{O(l)} \\rightleftharpoons \\text{H}_3\\text{O}^+\\text{(aq)} + \\text{A}^-\\text{(aq)}\\]  What is the percent ionization of \\(\\text{HA}\\) in this solution?"
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url: "https://nerd-notes.com/ubq/121392/"
date_modified: "2026-08-23T05:02:03+00:00"
---

# A student prepares a \(0.20\text{ M}\) aqueous solution of a weak monoprotic acid, \(\text{HA}\), with an acid-dissociation constant \(K_a = 2.0 \times 10^{-5}\) at \(25\ ^\circ\text{C}\). The ionization reaction is represented by the equation below.

\[\text{HA(aq)} + \text{H}_2\text{O(l)} \rightleftharpoons \text{H}_3\text{O}^+\text{(aq)} + \text{A}^-\text{(aq)}\]

What is the percent ionization of \(\text{HA}\) in this solution?

A student prepares a \(0.20\text{ M}\) aqueous solution of a weak monoprotic acid, \(\text{HA}\), with an acid-dissociation constant \(K_a = 2.0 \times 10^{-5}\) at \(25\ ^\circ\text{C}\). The ionization reaction is represented by the equation below.

\[\text{HA(aq)} + \text{H}_2\text{O(l)} \rightleftharpoons \text{H}_3\text{O}^+\text{(aq)} + \text{A}^-\text{(aq)}\]

What is the percent ionization of \(\text{HA}\) in this solution?

- **A.** \(0.010\%\)
- **B.** \(0.10\%\)
- **C.** \(0.20\%\)
- **D.** \(1.0\%\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/121392/*