A Discovery Approach to Three Organic Laboratory Techniques: Extraction, Recrystallization, and Distillation

This article describes three discovery-based experiments geared toward the beginning organic chemistry laboratory student. Each experiment focuses on one of the following purification techniques: extraction, recrystallization, or distillation. Unlike traditional purification-focused experiments whose goal is mastery of technique or optimization of results, the goal of these three experiments is students discovering for themselves the fundamental principles that underlie each technique. In each experiment, one or more parameters, such as solvent volume, time, or boiling point difference, is varied. Students compare the results of all variations and draw conclusions as to the underlying principles. The article concludes with an assessment of the effectiveness of these experiments.