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The Role of Mental-Modeling Ability, Content Knowledge, And THE ROLE OF MENTAL-MODELING ABILITY, CONTENT KNOWLEDGE, AND MENTAL MODELS IN GENERAL CHEMISTRY STUDENTS’ UNDERSTANDING ABOUT MOLECULAR POLARITY A Dissertation presented to the Faculty of the Graduate School University of Missouri – Columbia In Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy by CHIA-YU WANG Dr. Lloyd H. Barrow, Dissertation Supervisor AUGUST 2007 © Copyright by Chia-Yu Wang 2007 All Rights Reserved The undersigned, appointed by the Dean of the Graduate School, have examined the dissertation entitled. THE ROLE OF MENTAL-MODELING ABILITY, CONTENT KNOWLEDGE, AND MENTAL MODELS IN GENERAL CHEMISTRY STUDENTS’ UNDERSTANDING ABOUT MOLECULAR POLARITY Presented by Chia-Yu Wang A candidate for the degree of Doctor of Philosophy. And hereby certify that in their opinion it is worthy to acceptance. Lloyd H. Barrow ____________________________________________________________ Dr. Lloyd H. Barrow, Dissertation Supervisor Sandra K. Abell ____________________________________________________________ Dr. Sandra K. Abell Mark J. Volkmann ____________________________________________________________ Dr. Mark J. Volkmann David J. Robertson ____________________________________________________________ Dr. David J. Robertson Mark Ehlert ____________________________________________________________ Dr. Mark Ehlert ACKNOWLEDGEMENTS I first want to extend my deepest gratitude to my doctoral advisor, Dr. Lloyd Barrow, who set no limit allowing me to explore freely in science education research. I can’t thank you enough for your guidance and endless support throughout my entire doctoral program. You always stood by me and had faith in me. You have allowed me to grow at my own pace. I would also like to acknowledge my other committee members: Dr. Sandra Abell, Dr. Mark Volkmann, Dr. Mark Ehlert, and Dr. David Robertson. It is very difficult to express my thanks in a limited paragraph because each of you has contributed greatly to my knowledge and research ability of science education from different perspectives. What you have taught me is far beyond this dissertation work. Thank you Dr. Abell and Dr. Volkmann for being great models of mentors and researchers. Your friendship will always have a special place in my heart. Thank you Dr. Ehlert – my experience working with you on the professional development project has prepared me to have a critical eye to examine quantitative data and a sensitive mind to explore the dynamic interactions in an educational setting. Dr. Robertson, thank you for opening your class and offering your support throughout my study. The experiences of being a student and a researcher in your courses opened a window for me into the dynamic interactions of undergraduate chemistry classrooms. I also want to thank my science education colleagues for their friendship and all the joyful times that we have shared. Although I am not naming each of you, thank you for being there for me during my down times and cheering me up with your support and ii smiles. Pursuing my doctoral degree has become the greatest adventure of my life. Because of your company, this adventure has been full of joy and memories. I express my special appreciation to Catherine Wissehr, Meredith Park Rogers, Patrick Brown, Kusalin Musikul, Kristen Hutchins, and Hung Chiao. Thank you for editing my work and providing your insight at the various stages of my study. I also want to thank all of the participants in my study. Thank you for devoting your time and granting access to your information. Your participation was valuable to my study. Last, but not least, I want to thank my parents, Hsun-Chiu Shih and Hsun-Ming Wang, for supporting me in pursuing my dream. Hui-Yu, my sister, thank you for being the best friend I could ever have. You are the first person I want to share the great news with: Here I am, holding my degree. iii TABLE OF CONTENTS ACKNOWLEDGEMENTS................................................................................................ ii LIST OF TABLES........................................................................................................... xiv LIST OF FIGURES ......................................................................................................... xvi ABSTRACT................................................................................................................... xviii Chapter 1. INTRODUCTION .........................................................................................................1 Purpose of the Study and the Overarching Research Question .....................................3 Conceptual Framework..................................................................................................4 Fundamental Knowledge ......................................................................................4 Thinking with Mental Models ..............................................................................7 Definition of Terms........................................................................................................9 Significance of the Study.............................................................................................13 Assumptions.................................................................................................................15 Quantitative Phase ..............................................................................................15 Qualitative Phase ................................................................................................16 Limitations of the Study...............................................................................................18 Limitations of the Quantitative Method..............................................................18 Limitations of the Qualitative Method................................................................19 Organization of the Dissertation ..................................................................................20 2. LITERATURE REVIEW ............................................................................................22 Methods Used to Investigate Learners’ Mental Models..............................................22 Two-Tier Diagnostic Instruments.......................................................................23 Open-Ended Responses ......................................................................................27 iv Interviews with Probing Questions and Drawing ...............................................28 Interview Using Pictorial or Concrete Models for the Selection of Preferred Models ............................................................................29 Interview with a Problem Presented ...................................................................29 Interview-about-events (IAE) .................................................................30 Prediction-observation-explanation (POE).............................................31 Learning Impediments at the Submicroscopic-Symbolic Domain ..............................33 A Lack of an Integrated Conceptual Framework................................................33 Common Sense Reasoning .................................................................................37 Functional reduction and functional fixedness .......................................37 Use of anthropomorphic terms in chemical instruction..........................39 Insufficient Understanding for Chemical Representations and Models..........................................................................................................40 Lack of appreciation about role of models .............................................40 Abstraction and unfamiliarity with symbols...........................................41 Difficulty on shifting between/among chemical representations............42 A Low Visual-Spatial Thinking Ability .............................................................48 Summary......................................................................................................................49 3. METHODOLOGY ......................................................................................................52 Research Plan...............................................................................................................52 Research Questions and Null Hypotheses ...................................................................53 Quantitative.........................................................................................................53 Qualitative...........................................................................................................55 Context of the Study ....................................................................................................56 Course Structure..................................................................................................56 Concepts Associated with Molecular Polarity....................................................57 v Overall Design of the Study.........................................................................................60 Quantitative Research Phase........................................................................................61 Variables .............................................................................................................61 Instrumentation ...................................................................................................63 Participants..........................................................................................................65
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