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  • Misconceptions in Chemistry

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  • Hans-Dieter Barke l AlHazari l Sileshi Yitbarek

    Misconceptionsin Chemistry

    Addressing Perceptionsin Chemical Education

    1 3

  • Prof. Dr. Hans-Dieter BarkeUniversitat MunsterFB 12 Chemie und PharmazieInst. Didaktik der ChemieFliednerstr. 2148149 MunsterGermany

    Dr. Al HazariUniversity of TennesseeDept. Chemistry505 Buehler HallKnoxville TN 37996-1600USA

    Dr. Sileshi YitbarekKotebe College of TeacherEducationAddis AbabaEthiopia

    ISBN: 978-3-540-70988-6 e-ISBN: 978-3-540-70989-3

    DOI 10.1007/978-3-540-70989-3

    Library of Congress Control Number: 2008933285

    # Springer-Verlag Berlin Heidelberg 2009

    This work is subject to copyright. All rights are reserved, whether the whole or part of the material isconcerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation,broadcasting, reproduction on microfilm or in any other way, and storage in data banks.Duplication of this publication or parts thereof is permitted only under the provisions of theGerman Copyright Law of September 9, 1965, in its current version, and permission for use mustalways be obtained from Springer. Violations are liable to prosecution under the GermanCopyright Law.

    The use of general descriptive names, registered names, trademarks, etc. in this publication does notimply, even in the absence of a specific statement, that such names are exempt from the relevantprotective laws and regulations and therefore free for general use.

    Cover design: KunkelLopka GmbH

    Printed on acid-free paper

    9 8 7 6 5 4 3 2 1

    springer.com

  • We would like to dedicate this book toChemistry students everywhere. May theirquest to full understanding of this subjectlead them to the discovery of the truth andthe beauty of Chemistry.

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  • Acknowledgment

    First, we would like to cordially thank Dr. Hilde Wirbs, wife of Hans-DieterBarke, for all the discussions concerning chemistry misconceptions and for testingsome proposed strategies for teaching and learning in her school,Kaethe-KollwitzRealschule in Emsdetten near Muenster, Germany. Many thanks to colleaguesand friends: Prof. Dr. Dieter Sauermann (Munich), Prof. Dr. Guenther Harsch(Muenster) and Prof. Dr. Rebekka Heimann (Leipzig) who helped us get interest-ing insights into problems of chemistry education.

    Special appreciation goes to Barbara DoranRogel and Dr. Friedhelm Rogelfor translating all chapters of the German book on Chemical Misconceptions:Prevention and Cure, written by Hans-Dieter Barke into English. Same appre-ciation belongs to artist Mr. Mulugeta Gebrekidan, he did the drawings withregard to the concept cartoons.

    We are also gratefully indebted to Dr. Temechegn Engida, Dr. Birte Moeller,Dr. Nina Strehle, Dr. Cosima Kuhl, Dr. Wahyne Sopandi, Dr. Sebastian Musli,Dr. Claus Hilbing, Reinhard Roelleke, Tobias Doerfler and SerkalemGirma foravailing themselves whenever we needed their support.

    Finally we would like to thank the Fonds of Chemical Industries FCI inFrankfurt, Germany, and the German Society of Research DFG in Bonn,Germany. The financial support of the FCI allowed us to realize and to utilizeall the Masters theses as the research basis of the German book on ChemicalMisconceptions. The DFG supported our visits to Chemical Education con-gresses in the United States of America where we met Dr. Al Hazari, Universityof Tennessee, Knoxville.

    October 2008 Hans-Dieter Barke, Al Hazari, Sileshi

    vii

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  • Contents

    Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

    1 Perceptions of Ancient Scientists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91.1 The Theory of Basic Matter . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101.2 Transformation Concepts of the Alchemists . . . . . . . . . . . . . . . 101.3 The Phlogiston Theory. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111.4 Historic AcidBase Theories . . . . . . . . . . . . . . . . . . . . . . . . . . . 121.5 Horror Vacui and the Particle Concept . . . . . . . . . . . . . . . . . 141.6 Atoms and the Structure of Matter . . . . . . . . . . . . . . . . . . . . . . 15References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

    2 Students Misconceptions and How to Overcome Them . . . . . . . . . . . . 212.1 Students Preconcepts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 212.2 School-Made Misconceptions . . . . . . . . . . . . . . . . . . . . . . . . . . 242.3 Students Concepts and Scientific Language . . . . . . . . . . . . . . . 262.4 Effective Strategies for Teaching and Learning . . . . . . . . . . . . . 28References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33Further Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

    3 Substances and Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 373.1 Animistic Modes of Speech . . . . . . . . . . . . . . . . . . . . . . . . . . . . 383.2 Concepts of Transformation . . . . . . . . . . . . . . . . . . . . . . . . . . . 393.3 Concepts of Miscibility for Compounds . . . . . . . . . . . . . . . . . . 413.4 Concepts of Destruction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 433.5 Concepts of Combustion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 463.6 Concepts of Gases as not Substances . . . . . . . . . . . . . . . . . . . 503.7 Experiments on Substances and Their Properties . . . . . . . . . . . 52References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64Further Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

    4 Particle Concept of Matter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 674.1 Smallest Particles of Matter and Mental Models. . . . . . . . . . . . 694.2 Preformed and Non-preformed Particles . . . . . . . . . . . . . . . . . . 73

    ix

  • 4.3 Smallest Particles as Portions of Matter . . . . . . . . . . . . . . . . . . 764.4 Particles and the Horror Vacui . . . . . . . . . . . . . . . . . . . . . . . . 784.5 Particles Generic Term for Atoms, Ions and Molecules . . . . . 824.6 Formation of Particles and Spatial Ability . . . . . . . . . . . . . . . . 834.7 Diagnosis Test for Understanding the Particle Model of Matter 864.8 Experiments on Particle Model of Matter . . . . . . . . . . . . . . . . . 93References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99Further Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100

    5 StructureProperty Relationships . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1035.1 Structure and Properties of Metals and Alloys . . . . . . . . . . . . . 1035.2 Existence of Ions and Structure of Salts. . . . . . . . . . . . . . . . . . . 1085.3 Mental Models on Ionic Bonding . . . . . . . . . . . . . . . . . . . . . . . 1155.4 Chemical Structures and Symbolic Language . . . . . . . . . . . . . . 1255.5 Experiments on StructureProperty Relationships . . . . . . . . . . 130References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140Further Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142

    6 Chemical Equilibrium. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1456.1 Overview of the Most Common Misconceptions. . . . . . . . . . . . 1456.2 Empirical Research. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1466.3 Teaching and Learning Suggestions. . . . . . . . . . . . . . . . . . . . . . 1566.4 Experiments on Chemical Equilibrium . . . . . . . . . . . . . . . . . . . 165References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169Further Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170

    7 AcidBase Reactions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1737.1 AcidBase Reactions and the Proton Transfer . . . . . . . . . . . . . 1737.2 Misconceptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1757.3 Teaching and Learning Suggestions. . . . . . . . . . . . . . . . . . . . . . 1837.4 Experiments on Acids and Bases . . . . . . . . . . . . . . . . . . . . . . . . 193References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204Further Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204

    8 Redox Reactions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2078.1 Misconceptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2098.2 Teaching and Learning Suggestions. . . . . . . . . . . . . . . . . . . . . . 2178.3 Experiments on Redox Reactions . . . . . . . . . . . . . . . . . . . . . . . 226References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231Further Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232

    9 Complex Reactions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2359.1 Misconceptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2379.2 Teaching and Learning Suggestions. . . . . . . . . . . . . . . . . . . . . . 245

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  • 9.3 Experiments on Complex Reactions . . . . . . . . . . . . . . . . . . . . . 252References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259

    10 Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26110.1 Misconceptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26210.2 Empirical Research. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26510.3 Energy and Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26910.4 Fuel and Chemical Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27210.5 Experiments on Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 279References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 286Further Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287

    List of Experiments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 289

    Epilogue. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 293

    Contents xi

  • Introduction

    At last I found a lecture worth getting up early in the morning for; excellentexamples and experiments of teaching chemistry; now I know what chemistryeducation means and why it is so important for my studies; good to have theclear concept of the pie-chart at the beginning of all lectures [1]. These com-ments from would-be-chemistry teachers show that the lectures of chemistryeducation in our Institute of Chemistry Education at University of Muensterare extremely beneficial in assisting them in their approach to teaching chemistryat school.

    The most important subjects of 15 lectures in chemistry education can bepresented in a kind of pie-chart (see Fig. 0.1): Learners ideas andmisconcep-tions; experiments; structural and mental models; terminology, symbols andformulae; every-day-life chemistry; media; motivation; teaching aims [1].Because we want to put a lot of emphasis on the learner, she or he is thereforeplaced at the centre of the diagram. Secondly, scientific ideas should bereflected in association with appropriate teaching processes for the learner.Finally there should be reflections on the human element or context to eachsubject asMahaffy [2] has proposed. There are free sectors in that diagram formore chemistry education subjects to reflect upon. In this book emphasis isgiven to students preconceptions and misconceptions; experiments; structuraland mental models; terminology, symbols and formulae.

    In our experience of beginning of courses in chemistry education, would-be-chemistry teachers are often not clear about their own or students Preconceptsor misconceptions. They are not aware of how important it is to know moreabout these concepts and how to integrate them into chemistry education atschool. Our reason for publishing this book is to assist those studying to becomechemistry teachers and those already teaching chemistry at school. We alsosupport professor Jungs comments, a physics teacher in Germany: One shouldreally write a book on diagnosing misconceptions and give it to all teachers. Thepsychologist Langthalermade similar comments: If you, as a teacher,would havemore diagnostic abilities and tools, many problems with your students wouldnever even arise.

    In planning coursework in the past few decades, teachers were under theimpression that young pupils had hardly any knowledge of science. Therefore,

    H.-D. Barke et al., Misconceptions in Chemistry, DOI 10.1007/978-3-540-70989-3_0, Springer-Verlag Berlin Heidelberg 2009

    1

  • teachers had only to decide how to plan a lecture in order to transmit scientificideas to their pupils, perhaps incorporating laboratory experiments or newtechnology-based methods.

    However, research has found otherwise. Latest studies in science educationshow that children and adolescents have many images and ideas about natureand their own surroundings. Nieswandt [3], for example, states according to herresearch: Even from the very early days children are developing their own ideasabout nature and every-day life. They are looking at cause and effect, at whathappens if they let something fall to the floor, if they push, pull or throw things.By repeating these experiences, they develop a concept about the movement ofthings on the ground and in the air. Examination of these ideas and conceptsshows that they are often in conflict to those that are typically accepted by thescientific community. Research in the field of pre-school knowledge has shownthat these preconceptions of learning and comprehension tend to hinder theunderstanding of modern scientific concepts.

    Research in students conceptions in chemistry is based on the constructivistapproach to learning, in which students construct their own cognitive structure.According to this approach of learning, learners generate their own meaningbased on their background, attitudes, abilities, experiences etc, before, duringand after instruction. Since students do construct or build their own concepts,their constructions differ from the one that the instructor holds and has tried topresent.

    Fig. 0.1 Main subjects of a lecture in chemistry education, pie-chart metaphor [1]

    2 Introduction

  • These diffe...