Organic chemistry students’ resource selection across the submicroscopic and macroscopic domains

Abstract

Chemistry learning can be conceptualized as a pluralistic discipline that involves the coordination of different domains. Two of these domains that students regularly interact with when enrolled in chemistry courses are the submicroscopic and macroscopic. Prior literature suggests that students’ understanding of the relationship between these domains is often fragmented, resulting in varying explanations for macroscopic phenomena. Often times, these alternative explanations are simply categorized as incorrect. However, this dichotomous framing risks oversimplifying how students navigate the varying domains of chemistry and how the salient features within each domain might impact the way in which students draw on learned chemical principles. This study adopts a resources perspective that traces how students draw upon, adapt, and reconstruct their conceptual resources across tasks that cue students toward submicroscopic explanations and tasks that present students with macroscopic observations. To capture how students identify relevant resources within each of these task types, data were collected from ten participants through 60 minute semi-structured interviews. Each interview consisted of two sections: macroscopic tasks based on a video of an S_N1 laboratory experiment, and submicroscopic-cued tasks using bond-line structures of reagents. Across both task types, participants were asked to explain reaction outcomes and justify the chemical principles guiding their conclusions. Findings revealed that macroscopic cues significantly shaped how students evaluated reaction principles, even when drawing on the same conceptual resources used in the submicroscopic cued tasks. Additionally, students often drew on reactionary mnemonics learned in their lectures that provided minimal interpretative utility when viewing macroscopic observations. Consequently, reasoning unfolded as task-dependent, with varying degrees of parallel resource implementation across the domains. These results underscore the need for instructional designs that afford connections between the domains of chemistry, through prioritizing sensemaking over recall to encourage conceptual flexibility.