Implementation of a green chemistry practice for the teaching of spectrophotometry

Abstract

In the laboratory of Instrumental Analysis the topics of quantification of analytes by colorimetry are addressed, this practice was initially performed using potassium dichromate as a chemical reagent that is toxic and causes damage to the environment. Based on the objective of the practice (to facilitate the teaching of colorimetry) and to reduce the negative impact on the environment and the health of students, an alternative practice was designed that uses a red plant dye to replace the potassium dichromate; the dye is a low-cost and relatively harmless compound for both health and the environment. The practice was carried out with ten student volunteers, who worked individually, from the powder dye prepared a solution and then a series of dilutions to determine the concentration of a test sample. The experience could be carried out individually in work teams and the concentration of a problem sample provided could be determined. The implemented practice is a green alternative for teaching colorimetry in university students.