Laboratory Skills Assignments as a Teaching Tool to Develop Undergraduate Chemistry Students' Conceptual Understanding of Practical Laboratory Skills

Laboratory skills assignments were developed as a novel approach to providing students with the opportunity to engage in hands-on laboratory skills development outside of the lab during the COVID-19 pandemic. Initially, the assignments were implemented within a second-year forensic chemistry course of 48 students and redesigned and modified to be implemented within a large in-person second-year analytical chemistry course of 208 students as a complement to the laboratory experiments. Five laboratory skills were chosen to coincide with those used within the laboratory experiments of the course: pipetting, quantitative transfer, serial dilutions, buret use within titrations, and weight by-difference mass measurements. Each skills assignment consisted of two videos demonstrating the selected skill: one in which the skill was performed properly and one in which deliberate errors have been included. For each skills assignment, students were tasked with distinguishing between the two videos along with identifying the included errors and the consequences each error would have on either the accuracy and reproducibility of the collected data or the safety of the experimental procedure. Student feedback on the skills assignments is also reported.