Acid-base chemistry has a prominent role in the general chemistry curriculum and is one of the most challenging topics for general chemistry students. In this paper, we report on a laboratory experiment where students explore the acid-base properties of aqueous salt solutions. Students prepare seven aqueous salt solutions, measure the pH of each, and interpret the pH of each solution based on the hydrolysis reactions of the cations and anions present. Using the measured pH values, the students determine the hydrolysis constants of the various cations and anions and convert them to their respective pK’s. To ascertain the quality of their data, the students compare their results with the known pK values. The students also compare their average measured pH values to the theoretical pH values that they calculated. The students’ results from four general chemistry laboratory sections are presented and discussed.
Bazzi et al. (Wed,) studied this question.