---
title: "A student prepares an acetate buffer for an enzyme assay by mixing acetic acid, \\(\\text{CH}_3\\text{COOH}\\), and sodium acetate, \\(\\text{{NaCH}}_3\\text{COO}\\). The desired pH is \\(5.06\\), and the \\(pK_a\\) of acetic acid is \\(4.76\\). Assume that \\(\\log 2.0=0.30\\).  Using \\(\\text{pH}=pK_a+\\log\\left(\\dfrac{[\\text{CH}_3\\text{COO}^-]}{[\\text{CH}_3\\text{COOH}]}\\right)\\), what molar ratio of \\(\\text{CH}_3\\text{COO}^-\\) to \\(\\text{CH}_3\\text{COOH}\\) is required?"
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url: "https://nerd-notes.com/ubq/119541/"
date_modified: "2026-08-19T12:54:42+00:00"
---

# A student prepares an acetate buffer for an enzyme assay by mixing acetic acid, \(\text{CH}_3\text{COOH}\), and sodium acetate, \(\text{{NaCH}}_3\text{COO}\). The desired pH is \(5.06\), and the \(pK_a\) of acetic acid is \(4.76\). Assume that \(\log 2.0=0.30\).

Using \(\text{pH}=pK_a+\log\left(\dfrac{[\text{CH}_3\text{COO}^-]}{[\text{CH}_3\text{COOH}]}\right)\), what molar ratio of \(\text{CH}_3\text{COO}^-\) to \(\text{CH}_3\text{COOH}\) is required?

A student prepares an acetate buffer for an enzyme assay by mixing acetic acid, \(\text{CH}_3\text{COOH}\), and sodium acetate, \(\text{{NaCH}}_3\text{COO}\). The desired pH is \(5.06\), and the \(pK_a\) of acetic acid is \(4.76\). Assume that \(\log 2.0=0.30\).

Using \(\text{pH}=pK_a+\log\left(\dfrac{[\text{CH}_3\text{COO}^-]}{[\text{CH}_3\text{COOH}]}\right)\), what molar ratio of \(\text{CH}_3\text{COO}^-\) to \(\text{CH}_3\text{COOH}\) is required?

- **A.** \(0.50:1\)
- **B.** \(2.0:1\)
- **C.** \(3.0:1\)
- **D.** \(4.0:1\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/119541/*