The language of organic chemistry: is fluency the key to success?

In chemistry, like other sciences, we rely on symbols and other representations to communicate abstract, small, and dynamic phenomena. These representations become part of that discipline’s language; the electron-pushing formalism (EPF) is a central example in organic chemistry. Students can spend a large amount of time decoding chemistry’s symbolic language, increasing their working memory load. We believe this increased cognitive load limits their abilities to learn new concepts and engage in scientific reasoning. We hypothesized that greater fluency would reduce cognitive load, thus freeing cognitive resources for more advanced scientific reasoning. Our previous work has demonstrated that students can quickly gain fluency using a learning module dedicated to that purpose (OrgMech101). In this study, we explored how EPF fluency relates to cognitive load and reasoning ability, in a sample of second-year organic chemistry student participants (N = 36). Using an experimental design, participants in two groups completed identical pre- and post-tests, with different learning phases: group 1 (treatment) focused on EPF skills, while group 2 (control) focused on acid–base concepts. We assessed EPF fluency and reasoning ability while measuring cognitive load using eye-tracking technology to capture changes in participants’ average and maximum pupil diameters. Eye-tracking data were analysed using a custom-made Python script, and participants’ reasoning ability was analysed by categorizing their arguments based on complexity. The findings revealed a significant relationship between EPF fluency and cognitive load (ρ(31) = 0.322, p = 0.039), regardless of the assigned group—the higher the fluency, the lower the participant’s cognitive load. The treatment group participants also had significantly decreased cognitive load from the pre- to the post-test (Z = 2.098, p = 0.036). However, there was no significant difference in cognitive load between the groups when accounting for their initial cognitive load levels. Participants in the treatment group exhibited greater increases in reasoning ability compared to the control group, which may be due to more available cognitive resources upon becoming more fluent with the EPF (lower cognitive load), as seen by the increase in their post-test scores. The findings highlight the importance of helping students become fluent with respect to representations to facilitate effective information processing. Reducing cognitive load can be achieved by ensuring students develop a foundational understanding of the EPF and incorporating causal mechanistic reasoning questions to encourage chemical reasoning and improve organic chemistry education.