Dissertation
What are they seeing? How students predict and explain substitution and elimination reactions
University of Iowa
Doctor of Philosophy (PhD), University of Iowa
Spring 2023
DOI: 10.25820/etd.007081
Abstract
Reasoning about reaction mechanisms has been a noted difficulty for students in organic chemistry. Substitution and elimination reactions often represent the first time that students are required to think about the deeper reasoning behind these processes, but not much research has been done about how students broadly conceptualize these reactions. Here, we focus on developing a description of the ways that students conceptualize bimolecular and unimolecular substitution and elimination reactions. Through the lens of coordination class theory as a theoretical framework, our analysis identifies the visual features students attend to and knowledge they coordinate when reasoning about reaction mechanisms across multiple tasks. Based on the data gathered from ten semi-structured student interviews, we developed representations of the ways students conceptualize the four reaction mechanisms and how they explained and predicted those reaction mechanisms on exam-type tasks. Our data indicates that across tasks, students place a heavier emphasis on the importance of the starting substrate in the outcome of a reaction but less focus on the function of the nucleophile or base in each reaction. Students need support in reasoning about all species in a reaction mechanism and coordinating those features when making predictions about a reaction’s outcome. Based on this, we provide implications for researchers and practitioners.
Details
- Title: Subtitle
- What are they seeing? How students predict and explain substitution and elimination reactions
- Creators
- Kevin H. Hunter
- Contributors
- Nicole Becker (Advisor)Renée Cole (Committee Member)Tori Forbes (Committee Member)Matthew Lira (Committee Member)Florence Williams (Committee Member)
- Resource Type
- Dissertation
- Degree Awarded
- Doctor of Philosophy (PhD), University of Iowa
- Degree in
- Chemistry
- Date degree season
- Spring 2023
- Publisher
- University of Iowa
- DOI
- 10.25820/etd.007081
- Number of pages
- xii, 121 pages
- Copyright
- Copyright 2023 Kevin H Hunter
- Language
- English
- Date submitted
- 04/18/2023
- Date approved
- 06/30/2023
- Description illustrations
- illustrations, tables
- Description bibliographic
- Includes bibliographical references (pages 79-88).
- Public Abstract (ETD)
- This dissertation project is focused on understanding the ways that students in organic chemistry reason about foundational reaction pathways. Using semi-structured interviews, I characterized the visual features that students attend to and the knowledge they use to reason about substitution and elimination reactions. Analysis shows that students more heavily attend to specific parts of the reactions without wholistically considering all the factors that influence a reaction’s outcome. This work will allow instructors to better understand students’ needs and provide the tools for them to leverage students’ productive knowledge, helping to develop the scientific practice of constructing explanations from evidence.
- Academic Unit
- Chemistry
- Record Identifier
- 9984428941902771
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