Show Me You Can Do It: Practical Examinations for Senior Organic Chemistry Laboratory Courses

Abstract

Written examinations for laboratory courses fall short in testing students’ technical skills, problem-solving abilities, and execution of experimental design. This has led to practical examinations growing in popularity, but examples for senior-level students remain scarce. Senior organic chemistry students are gearing toward independence to design and execute their own experimental procedures. Thus, an examination reflective of key aspects of an experimental procedure is suitable for such students. The key stages identified in most organic reaction processes are as follows: the design and assembly of the experiment, the execution of the reaction, the workup, the purification, and data analysis of the isolated product(s). Time constraints in an examination make implementing all these stages generally unfeasible. Herein are presented two different practical examinations for third and fourth year level students in an organic chemistry laboratory. To ensure students had adequate time to complete the exam, some stages of the organic reaction process were removed (e.g., the reaction execution), or partially removed, with a focus on the key learning outcomes of the lab course. In addition, a comparison of the course and exam averages is included to illustrate alignment between students understanding throughout the term as compared to the final exam. Finally, a summary of student perceptions of the exams via survey data collected from students is also incorporated. Student’s perceptions are compared to observations made by the instructor and teaching assistants.