In this Activity, students investigate concentration levels by using serial dilution to prepare several solutions of presweetened powdered drink mix. Students taste the solutions to determine at which concentration they first discern the sweetness. A connection is also made to the concentration of pollutants in air. This Activity can be used as a precursor to discussing concentration and dilution, and the idea of parts per million, and correlates well with discussions on air and water pollution.
Mindy Bedrossian, J. Chem. Educ. 2005, 82, p240A.