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Electrostatic potential maps (EPM) have the potential to support organic chemistry students in seeing reaction mechanisms through the perspective of electrostatic attraction. Prior to any pedagogical changes, foundational knowledge on how students use EPMs in particular contexts would be needed to inform how to integrate EPMs into instruction. This study describes an exploration into how organic chemistry students use EPMs during two card sort tasks. Seventeen undergraduate organic chemistry students participated in an interview that included an open and closed card sort. The interviews were inductively coded to identify students’ usage of EPMs, and usage change based on the open sort compared to the closed sort. Viewed from a resources framework, this study demonstrated how students’ use of EPMs shifted depending on the task structure. Variations were observed both among students and within students between tasks in terms of whether EPMs were utilized and when utilized whether information from EPMs were used in isolation or integrated with other chemistry concepts. The results of this study imply that more formal integration of EPMs into instruction and assessment would be needed for students who did not use EPMs. Instruction that models and assesses translation of representations may begin activating a more integrated perspective of EPMs which could be productive for students who had an isolated use of EPMs. The introduction of EPMs independent of specific chemistry tasks (e.g.during a general introduction of molecular representations) could lead some students to focus only on explicit features of the EPM representation and not tie features of the representation to their existing chemical knowledge.
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Affordances of Electrostatic Potential Maps in Promoting Use of Electronic Features and Causal Reasoning in Organic Chemistry
Instructional materials in organic chemistry include a wide variety of representations, such as chemical formulas, line-angle diagrams, ball-and-stick diagrams, and electrostatic potential maps (EPMs). Students tend to focus on explicit features of a representation while they are reasoning about chemical concepts. This study examined the affordances of electrostatic potential maps in students’ approaches when the maps were integrated into four foundational organic chemistry problems using an experimental design approach. First-semester organic chemistry students were surveyed from two different institutions, where they made predictions and explained their reasoning behind identifying an electrophilic site, predicting the product, selecting the faster reaction, and classifying a mechanism. Students were randomly assigned to one of four surveys that differed by the representation they were given for the prompts: chemical formula, line-angle diagram, ball-and-stick diagram, and EPM. Responses from students with EPMs were analyzed and compared to responses from students with the non-EPM representations. Results indicated that students with EPMs had higher performance depending on the problem. They were also more likely to cite electronic features such as electron density, nucleophilicity, etc., and were more likely to use causal reasoning in their explanations. This study offers evidence in support of affordances of EPMs in promoting students’ use of electronic features and causal reasoning. This evidence adds to the chemistry education literature by offering a potential means for promoting students’ use of electronic features and causal reasoning by incorporating EPMs into assessment items. Implications for instruction include using EPMs in both instruction and assessment as a tool to help students build skills around invoking electrostatics and causal reasoning to solve problems in organic chemistry.
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- PAR ID:
- 10571869
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- Journal of Chemical Education
- Volume:
- 101
- Issue:
- 9
- ISSN:
- 0021-9584
- Page Range / eLocation ID:
- 3691 to 3702
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/acs.jchemed.4c00500
