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UC San Diego UC San Diego Electronic Theses and Dissertations UC San Diego UC San Diego Electronic Theses and Dissertations Title Students' ways of understanding aromaticity and electrophilic aromatic substitution reactions Permalink https://escholarship.org/uc/item/8mb6v54x Author Duffy, Anne Merete Publication Date 2006 Peer reviewed|Thesis/dissertation eScholarship.org Powered by the California Digital Library University of California UNIVERSITY OF CALIFORNIA, SAN DIEGO SAN DIEGO STATE UNIVERSITY STUDENTS’ WAYS OF UNDERSTANDING AROMATICITY AND ELECTROPHILIC AROMATIC SUBSTITUTION REACTIONS A dissertation submitted in partial satisfaction of the requirements for the degree of Doctor of Philosophy in Mathematics and Science Education by Anne Merete Duffy Committee in charge: University of California, San Diego Professor Barbara Sawrey, Chair Professor Guershon Harel Professor Edwin Hutchins San Diego State University Professor Fred Goldberg Professor Joanne Lobato 2006 Copyright Anne Merete Duffy, 2006 All rights reserved. SIGNATURE PAGE The dissertation of Anne Merete Duffy is approved, and it is acceptable in quality and form for publication on microfilm: ___________________________________________ ___________________________________________ ___________________________________________ ___________________________________________ ___________________________________________ Chair University of California, San Diego San Diego State University 2006 iii DEDICATION To God. To my husband, Dan Regan. And to my girls, Holly and Jill. All of whom provided love, support and understanding throughout the entire process of this doctoral program. I could not have done this without them by my side. I love you all very much. iv TABLE OF CONTENTS SIGNATURE PAGE.....................................................................................................iii DEDICATION ..............................................................................................................iv TABLE OF CONTENTS ...............................................................................................v LIST OF FIGURES........................................................................................................x LIST OF TABLES .......................................................................................................xii ACKNOWLEDGEMENTS ........................................................................................xiii VITA............................................................................................................................xvi ABSTRACT FOR THE DISSERTATION................................................................xvii CHAPTER 1: INTRODUCTION...................................................................................1 Background in Organic Chemistry.............................................................................1 Students’ Tendency Toward Memorization ...........................................................1 Conceptual Understanding in Chemistry................................................................4 Problem Statement and Research Questions ..............................................................8 Research Questions ..............................................................................................10 Why Aromaticity and Electrophilic Aromatic Substitution Reactions?...........10 DNR-Based Instruction and Its Fundamental Principles..........................................12 The Triad of Determinants ...................................................................................13 Mental Act........................................................................................................13 Ways of Understanding and Ways of Thinking ...............................................14 Three Instructional Principles of the DNR System ..............................................18 The Duality Principle .......................................................................................18 The Necessity Principle....................................................................................20 The Didactical Contract....................................................................................22 The Repeated Reasoning Principle...................................................................23 Significance for the Field of Chemistry Education ..................................................24 Overview of the Dissertation....................................................................................26 CHAPTER 2: REVIEW OF LITERATURE ...............................................................28 Introduction ..............................................................................................................28 Conceptual Understanding in Physics Education.....................................................29 Conceptual Understanding in General Chemistry Education...................................31 Conceptual Understanding and Student Performance on Exams .....................32 v Conceptual Understanding of Covalent Bonding.............................................34 Conceptual Understanding of Molecular Geometry.........................................37 Overview of Research in Organic Chemistry Education .........................................40 Spatial Visualization and Molecular Structure.................................................40 Problem-Solving in Organic Synthesis ............................................................43 Teaching Effects on Performance ....................................................................46 Conceptual Understanding in Organic Chemistry....................................................48 Concepts versus Algorithms: Analogs in Organic Chemistry..........................49 DNR-Based Instruction and Chemistry Education...................................................52 Constructivism in Chemistry Education...............................................................52 Chemistry Education and Harel’s DNR ...............................................................53 Ways of Thinking in Science Education ..............................................................56 Conclusion................................................................................................................59 CHAPTER 3: METHODOLOGY................................................................................61 General Research Perspective ..................................................................................61 Overview of the Research Setting ............................................................................63 Phase I Methodology................................................................................................63 Recruitment of Participants ..................................................................................63 Data Collection.....................................................................................................67 Data Analysis........................................................................................................69 Summary of Methodology for Phase I .................................................................70 Phase II Methodology...............................................................................................71 The Instrument Design .........................................................................................71 Data Collection.....................................................................................................73 Data Analysis........................................................................................................73 Phase II Summary.................................................................................................74 Phase III Methodology .............................................................................................75 The Experimental Design.....................................................................................75 Recruitment of Participants and Context..............................................................77 Data Collection.....................................................................................................79 Data Analysis........................................................................................................79 Summary of Phase III Methodology ....................................................................82 Summary of Dissertation Methodology ...................................................................82 CHAPTER 4: RESULTS ON STUDENTS’ WAYS OF UNDERSTANDING AROMATICITY AND ELECTROPHILIC AROMATIC SUBSTITUTION REACTIONS................................................................................................................84 Students’ Ways of Understanding Aromaticity........................................................85 Characteristics of Aromatic Compounds..............................................................85 Symbolic Characteristics of Aromatic Compounds .........................................86 Structural Characteristics of Aromatic Compounds.........................................91 vi Identifying Aromatic Compounds........................................................................98 Recognition of Structure by Recall or Analogy ...............................................99 Identification Based on Structural Considerations.........................................100 Universal Application of Hückel’s Rule ........................................................102
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