Electrochemical Quantification of Acetaminophen: An Engaging Cyclic Voltammetry Laboratory for the Quantitative Analysis Course

An engaging, simple, and cost-effective laboratory experiment has been implemented at our institution to teach undergraduate chemistry students about cyclic voltammetry and electrochemistry in general. This experiment involves the application of cyclic voltammetry to analyze a sample of acetaminophen (APAP) with the objective of determining the mass of APAP in a tablet of over-the-counter medication. During five semesters, students working in groups of typically four students each, carried out the experiment as part of their coursework in the laboratory. Seven out of ten groups reported results containing the expected value of 500 mg APAP per tablet in their calculated 95% confidence intervals. Students completed a 10-question quiz at the beginning of the semester and a similar one at the end of the semester. The scores of pre- and postcourse evaluations, which include 10 questions on basic general chemistry quantitative concepts, had an average percent change of 99.2% after, from a 50.7% average percent change before, laboratory implementation. The growth in normalized learning gains in classes performing this experiment also increased by 10.8%.