Clock Reaction: Outreach Attraction

Abstract

Chemistry students are often introduced to the concept of reaction rates through demonstrations or laboratory activities involving the well-known iodine clock reaction. For example, a laboratory experiment involving thiosulfate as an iodine scavenger is part of the first-year general chemistry laboratory curriculum at Dalhousie University. With the necessary materials, expertise, and laboratory space readily available, this undergraduate clock reaction experiment was modified to make it accessible to grade 9 students. The revised, qualitative experiment has been performed as an on-campus outreach initiative with eight grade 9 classes, reaching a total of 250 students, teachers, parents, and aides. The activity was facilitated by graduate student volunteers, who assisted the grade 9 students as they were exposed to a colorful adventure involving kinetics, chemical reactions, and catalysis. In general, adapting undergraduate experiments offers researchers and educators a positive and efficient way to introduce younger students to a university chemistry laboratory.