Why comparing matters – on case comparisons in organic chemistry

Abstract

When working with domain-specific representations such as structural molecular representations and reaction mechanisms, learners need to be engaged in multiple cognitive operations, from attending to relevant areas of representations, linking implicit information to structural features, and making meaningful connections between information and reaction processes. For these processes, appropriate instruction, such as a clever task design, becomes a crucial factor for successful learning. Chemistry learning, and especially organic chemistry, merely addressed meaningful task design in classes, often using more reproduction-oriented predict-the-product tasks. In recent years, rethinking task design has become a major focus for instructional design in chemistry education research. Thus, this perspective aims to illustrate the theoretical underpinning of comparing cases from different perspectives, such as the structure-mapping theory, the cognitive load theory, and the variation theory, and outlines, based on the cognitive theory of multimedia learning, how instructors can support their students. Variations of this task design in the chemistry classroom and recommendations for teaching with case comparisons based on current state-of-the-art evidence from research studies in chemistry education research are provided.

Evaluation of the Open-Ended Green Chemistry Generic Comparison (GC)2 Prompt for Probing Student Conceptions about the Greenness of a Chemical Reaction

“…29 For further details on the theoretical underpinning and advantages of using case comparisons, refer to the recent work of Graulich and Lieber. 30 Within chemistry, chemical reaction case comparison prompts allow students to mirror the actual inquiry process of organic chemists who often use competitive experiments to uncover reaction mechanisms, allowing students to gain a deeper understanding of the defining features of the reaction and subsequent mechanism. 28 Similarly, as shown in Figure 1, chemists must also consider the greenness of their chosen reaction materials and conditions and identify whether greener alternatives exist based on the 12 GCPs.…”

“…Furthermore, case comparison activities have been shown to lead to greater learning outcomes than traditional instruction because they prompt students to focus on comparing case features, thus allowing students to generate a schema for the concept that can be applied to new situations . For further details on the theoretical underpinning and advantages of using case comparisons, refer to the recent work of Graulich and Lieber …”

“… 29 For further details on the theoretical underpinning and advantages of using case comparisons, refer to the recent work of Graulich and Lieber. 30 …”