A pH curve is obtained when a base is titrated with an acid or an acid is titrated with a base. During an acid base titration, a solution with a known concentration (the titrant) is added slowly to a solution that has an unknown concentration. The sample being titrated undergoes changes in pH as the titration proceeds. These changes in pH are measured and then plotted against the volume of titrant added. The result is a pH curve, sometimes called a titration curve. By studying the pH curves, we can gain important information about acid-base reactions.

Titration is used to determine the concentration of an unknown solution. In Unit C, you used titration to study redox reactions. Titrations can also be applied to acid-base chemistry.