Chapter 1.

Overview

Acid–Base Titration Curves: Determining pK_a

The learning objectives of this experiment are as follows:

• Follow a titration progression using a pH meter, recording the pH changes as more titrant is added.
• Use titration data to plot the titration curve to extract the pH at the equivalence point and the pH at ¼, ½, and ¾ of the equivalence point.
• Utilize the Henderson–Hasselbalch equation to determine the pK_a of the acid analyte.

The Department of Chemistry and Biochemistry

The Ohio State University

Intro

We continue our discussion of acid–base chemistry by looking more carefully at a titration. In this lab you will be following the progression of a titration of a weak acid with a strong base by monitoring the pH and constructing a titration curve. We will use our data to study several regions of the curve and determine the pK_a for this weak acid.

Procedure

Credits