Acting Chromatography

Abstract

Chromatography is the most common analytical technique able to identify and quantify a wide gamut of substances in food, environmental, forensic, pharmaceutical, and many other kinds of real samples. We propose a simple drama science activity: students embody different compounds wearing emblems of different colors and dramatize their chromatographic separation. They cross the same path at the same speed when they walk, thereby mimicking the fate of molecules in the mobile phase; every now and then, they sit for different times on the chairs along the path, mimicking the adsorption process onto the active sites of the chromatographic bed; the average dwell time is different for different compounds. In this way, students get separated into different groups as they move along the path representing the chromatographic column; as they cross the exit, they trigger musicians to act as a detector: the artists actually play notes (signals) of different pitches and loudness, respectively, for different impersonated substances and amounts. The proposed gamification is appropriate for introductory high school chemistry, and it was carried out within the Content and Language Integrated Learning (CLIL) framework. Still, it can also be played by children (elementary or middle school) in outreach events if math implications are not dealt with. The learning objectives are (i) to make students aware of the chromatography principles and the mechanism the molecules undergo during their chromatographic run, (ii) to make the students explore the influence of experimental parameters on the chromatographic outcome, and (iii) to prevent common misconceptions about the causes of the chromatographic separation. Acting chromatography does not claim to reproduce the reality; it stimulates students to figure out microscopic facets of this macroscopic analytical technique that deserve proper attention. Videomaking is highly appreciated by digital native students; stage performances during outreach events are service-learning aspects involved in this educational activity, which bring about positive emotional energy and stimulate greater engagement.