the role of mental-modeling ability, content knowledge, and mental models in general chemistry ...

306 Pages·2007·1.31 MB·English

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
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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.

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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
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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
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Overall Design of the Study.........................................................................................60
Quantitative Research Phase........................................................................................61
Variables.............................................................................................................61
Instrumentation...................................................................................................63
Participants..........................................................................................................65
Data Collection...................................................................................................66
Reliability analysis..................................................................................66
Statistical analysis of data.......................................................................67
Qualitative Research Phase..........................................................................................68
Research Tradition..............................................................................................68
Role of the Researcher........................................................................................71
Data Collection...................................................................................................72
Interview implementation.......................................................................74
Data Analysis......................................................................................................76
Analyses of participants’ conceptual frameworks..................................77
Trustworthiness...................................................................................................81
Summary......................................................................................................................82
4. FINDINGS...................................................................................................................83
Introduction..................................................................................................................83
Quantitative Phase.......................................................................................................83
Descriptive Statistics....................................................................................................83
Analysis of Individual Instruments..............................................................................87
Instrument EN.....................................................................................................87
An alternative notion of stability............................................................87
An alternative electrostatic principle – Conservation of force...............90
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Applying Coulombic principle...............................................................91
Instruments CB and GP......................................................................................92
The octet rule and chemical bonds..........................................................94
Bond polarity..........................................................................................97
Molecular shape......................................................................................99
Polarity of molecules..............................................................................99
Intermolecular forces............................................................................100
Ionic lattices..........................................................................................101
Inferential Statistics...................................................................................................101
Qualitative Phase.......................................................................................................107
Findings of General Chemistry Students’ Mental-Modeling Ability,
Conceptual Frameworks, and Mental Models about Molecular Geometry
and Polarity................................................................................................................107
Characteristics of Students’ Mental-Modeling Ability While Thinking
About Concepts of Molecular Geometry and Polarity..............................................110
High Mental-Modeling Ability Group (HMMA Group)..................................111
Students in the HMMA group could construct a mental model of
a given molecule with or without a 2D representation
(Characteristic 1a).................................................................................111
Students in the HMMA group were able to reconstruct,
manipulate, or adjust a mental model accordingly by imposing
propositions or conditions of the problem on the model
(Characteristic 2a).................................................................................112
HMMA students were able to recognize their approaches to the
problem and constantly monitor their processes of reasoning and
construction of mental models (Characteristic 3).................................114
Also, these HMMA students self-checked and verified their
mental models and answers using an alternative approach if the
given molecule was relatively novel to them (Characteristic 4)...........116
Moderate Mental-Modeling Ability Group (MMMA Group)..........................117
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Students in the MMMA group constructed a 2D Lewis structure
before a mental model was generated. When the students were
familiar with the geometry of a given molecule, they could form
a mental model without seeing the 2D representation
(Characteristic 1b).................................................................................117
Students in the MMMA group had some degree of ability to
manipulate their mental model when compared to students in the
HMMA group, but sometimes, these students neglected to
review the problem and problem-solving processes carefully.
Therefore, they held on to a rigid mental model rather than
modifying or adjusting it based on the new condition in the
problem (Characteristic 2a & 2b).........................................................118
Limited or no monitoring for their mental-modeling processes
was observed among the MMMA students (Characteristic 3)..............119
Also, self-checking their mental models and answers using an
alternative approach was not apparent to these students (see
Table 21) (Characteristic 4)..................................................................120
Low Mental-Modeling Ability Group (LMMA Group)...................................122
Students in the LMMA group constructed a mental model by
recalling the geometry of a given molecule algorithmically based
on cues such as numbers of lone pairs and bonds in its 2D Lewis
structure. Often, these students did not form a mental model
(Characteristic 1)...................................................................................122
The LMMA students preferred to draw a 2D Lewis dot structure
on paper as a tool of thinking and then apply propositions or
conditions of a problem to the 2D Lewis dot structure for
inference (Characteristic 2)...................................................................124
The LMMA students did not monitor their processes of mental
modeling. At the end of the inference or reasoning, these
students did not perform self-checking to test or inspect mental
models or 2D representations using an alternative approach
(Characteristics 3&4)............................................................................127
Levels of Content Knowledge about Molecular Geometry, Polarity, and
Prerequisite Concepts.................................................................................................127
Conceptual Frameworks for Students with High Content Knowledge (refer to
JS’s, RE’s, and CR’s concept webs, Figure 6-14)............................................128
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