UC San Diego
Students' ways of understanding aromaticity and electrophilic aromatic substitution reactions
- Author(s): Duffy, Anne Merete
- et al.
Studies in organic chemistry education focus mainly on increasing students' performance. Studies from general chemistry education reveal that students' performance is not a good indicator of conceptual understanding. In support, Bhattacharyya and Bodner (2005) reveal that chemistry graduate students can produce correct answers to reaction mechanisms tasks in organic chemistry without understanding the underlying concepts behind the tasks. This dissertation uses the constructs of Harel's DNR-based instruction (1998, 2001, in press [a]) to categorize students' ways of understanding aromaticity and electrophilic aromatic substitution reactions. DNR refers to three instructional principles: Duality Principle, Necessity Principle and Repeated Reasoning Principle. Primarily, this study applies the following constructs integral to the Duality Principle: ways of understanding and ways of thinking. The purpose of this study is three- fold. The first purpose is to identify students' ways of understanding aromaticity and electrophilic aromatic substitution reactions and subsequently the ways of thinking that are inferred by these ways of understanding. The second purpose of this study is to provide quantitative evidence of students' beliefs (one category of ways of thinking) about learning organic chemistry. The third purpose is to show how we can help students develop more desirable ways of understanding aromaticity. First, several ways of understanding were identified from semi- structured interviews conducted with 12 undergraduate- level students. Three ways of thinking were inferred from these ways of understanding: 1) non-referential symbolic reasoning, 2) non-referential use of terminology, and 3) beliefs about learning organic chemistry. Second, the results of a 46-Item Likert Scale survey provided empirical evidence to support the claim that the students have a tendency towards memorization when learning organic chemistry. Third, this study demonstrated the potential for students' developing more scientific ways of understanding aromaticity through teaching interview sessions where problem tasks were designed to perturb students existing ways of understanding