1516L - Potentiometric Determination of pKa

In this experiment you will use the pH electrode (below left) and the drop counter (below right) attached to the MicroLab analysis box in order to titrate an acid against a base. You will then use the data collected to find the pKa of an unknown acid solution.

Additional details for this experiment, including the use of the pH probe and drop counter, are found here.

The instructions for which solutions to use are found in the Catalyst lab manual.

The Experiment Setup

Be careful with the pH probes, since they are delicate, and also check with your TA to ensure that your apparatus is constructed correctly. The basic experiment setup looks like this:

When the experiment is complete, dispose of any waste, return the pH probe and drop counter to the front bench and clean up the balance room and your work area as needed.