Essentials of Chemical Education

.

Hans-Dieter Barke • G€unther HarschSiegbert Schmid

Essentials of ChemicalEducation

Translated by Hannah Gerdau

Prof.Dr. Hans-Dieter BarkeWestf. Wilhelms-Universit€atM€unsterInstitut f€ur Didaktik der ChemieFliednerstr. 2148149 MunsterGermanybarke@uni-muenster.de

Dr. Siegbert SchmidUniversity of SydneySchool of ChemistrySydney New South WalesBldg. F11Australias.schmid@chem.usyd.edu.au

Prof.Dr. G€unther HarschWestf. Wilhelms-Universit€atM€unsterInst. f€ur Didaktik der ChemieFliednerstr. 2148149 M€unsterGermanyharsch@uni-muenster.de

Translated byHannah Gerdau214 Rue de Charenton75012 ParisFrance

Completely revised and updated English edition of the German title: Chemiedidaktik Heute byH.-D. Barke und G. Harsch, published by Springer-Verlag Heidelberg 2001

ISBN 978-3-642-21755-5 e-ISBN 978-3-642-21756-2DOI 10.1007/978-3-642-21756-2Springer Heidelberg Dordrecht London New York

Library of Congress Control Number: 2011939999

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Prologue

“That was my first lecture for which I did not mind to get up early in the morning, . . . wesaw meaningful presentations with many experiments and structural models for schoolchemistry,. . . a seminar where I really learnt a lot for my later profession, . . . it was goodfor our orientation to have the pie chart in the first lecture . . .”

These and other statements of students in a one-semester unit towards a qualifica-

tion as a chemistry teacher at the University of M€unster in Germany encouraged us

to write this book and to translate it into English. The content covers a broad range

of chemical education knowledge and many applications concerning chemistry

teaching at secondary level. We hope that apart from lecturers and students at

v

universities and colleges chemistry teachers in secondary schools will also benefit

from this book.

There is no single best order of contents in chemical education. Important

chapters like “students’ misconceptions, teaching aims, motivation, media,

experiments, models, chemical symbols and chemistry in everyday life” are linked

in many aspects: a linear order does not do justice to all these connections.

Therefore a group of scientists in the Society of German Chemists GDCh used a

pie chart to organise the chapters mentioned before (see first picture): these various

chapters can be taught in nearly every order the lecturer likes. The pie chart is

explained in detail in the following introduction chapter.

All reflections referring to these levels contain many examples of practical

teaching of chemistry at school. Especially a lot of experiments and many models

or model drawings showing aspects of the structure of matter should help develop-

ing mental models in the cognitive structure of the chemistry-teacher students or

later of the learners at school.

Because of the pie-chart metaphor the lecturers can create their own ideas of

teaching the “slices of the pie”: one may start with “students’ misconceptions”, the

other may start with “teaching aims” – it is up to them, in which order the “slices”

are taught. It is also our intention to keep some sectors that are not occupied by a

special topic: the lecturer may fill these gaps with their own ideas or contents, for

example with the topic “Assessment in chemical education” or “Curriculum

development”.

At the end of each of the first eight chapters we offer short “problems and

exercises”, which the students of the seminar may solve and discuss for a repitition

or for the final exam. At the end of most chapters there are also short procedures for

the experiments, which may be shown during the lecture or seminar. For inexperi-

enced students the descriptions of these experiments are so short that they will need

to consult additional lab manuals for a successful performance and for appropriate

waste treatment.

Chapters 9 and 10 are in addition to the pie-chart seminar – these chapters show

special views of the authors on two important issues of chemical education. In

Chap. 9 the method of Inquiry learning is linked to the introduction of Organic

chemistry in schools or at university level. In Chap. 10 the Structure-orientedapproach of chemistry education is introduced, especially sphere packings of

infinite structures and ions as smallest particles of salt crystals are described and

the corresponding structural models are discussed. These structural models may

help to train the spatial ability of students so that they are able to develop three-

dimensional mental models for a better understanding of formulae and equations in

chemistry.

We thank Mrs. Hannah Gerdau very much for doing most of the translation from

the original German book “Chemiedidaktik Heute” into the English language. She

took a lot of care to preserve the intentions of the original; she also adapted specific

German aspects of chemical education to those which are more common and known

in the in England, UK and US.

vi Prologue

We hope that lecturers of many universities in many countries – where English is

spoken in lectures and seminars – will use ideas from our book for their chemical

education. Please tell us if any important aspects are missing: we would be very

happy to add them in the next edition!

Muenster and Sydney Hans-Dieter Barke

G€unther HarschSiegbert Schmid

Prologue vii

.

Contents

1 Learners Ideas and Misconceptions . . . . . . . . . . . . . . . . . . . . . . . . . 1

1.1 Scientific Ideas: Theories of Science History . . . . . . . . . . . . . . . . 3

1.2 Learner: Empirical References of Student Conceptions . . . . . . . . 8

1.3 Teaching Processes: Considering Students’ Conceptions . . . . . . . 17

1.4 Human Element: Students’ Conceptions

and Everyday Language . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

2 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

2.1 Learner: Development, Attitudes, and Preconcepts . . . . . . . . . . . . 42

2.2 Teaching Processes: Opportunities to

Create Intrinsic Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

2.3 Scientific Ideas: Experimental Skills . . . . . . . . . . . . . . . . . . . . . . 49

2.4 Human Element: Motivation Through Everyday

Language and Media . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

3 Teaching Aims . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

3.1 Scientific Ideas: Teaching Goals and Their Dimensions . . . . . . . . 62

3.2 Human Element: Guidelines and Curricula . . . . . . . . . . . . . . . . . 67

3.2.1 Germany . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

3.2.2 USA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

3.2.3 England and the United Kingdom . . . . . . . . . . . . . . . . . . 75

3.3 Learner: Cognitive Development, Preconceptions,

Attitudes, Interests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

3.4 Teaching Processes: Variety of Methods for Realizing

Teaching Goals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

ix

4 Media . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93

4.1 Teaching Processes: Variety of Media for Chemistry Lessons . . . 96

4.2 Scientific Ideas: Appropriateness of Media . . . . . . . . . . . . . . . . . 103

4.3 Learner: Media and the Ability for Abstract Thinking . . . . . . . . . 105

4.4 Human Element: Mass Media . . . . . . . . . . . . . . . . . . . . . . . . . . . 111

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

5 Experiments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

5.1 Scientific Ideas: Experiments, Experimental Skills, Safety . . . . . . 121

5.2 Teaching Processes: Purpose, Selection Criteria, and Forms

of Experiments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129

5.3 Learner: Play Instinct, Curiosity, Experimental Skills . . . . . . . . . 135

5.4 Human Element: Environmental, Everyday Life,

and Historical Aspects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151

6 Structural and Mental Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153

6.1 Scientific Ideas: Thinking in Models . . . . . . . . . . . . . . . . . . . . . . 155

6.2 Teaching Processes: Models and Their Functions . . . . . . . . . . . . 165

6.3 Learner: Experience with Models . . . . . . . . . . . . . . . . . . . . . . . . 176

6.4 Human Element: Interdisciplinary Mental Models . . . . . . . . . . . . 177

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185

7 Scientific Terminology and Symbols . . . . . . . . . . . . . . . . . . . . . . . . . 189

7.1 Scientific Ideas: Parameters, Units, Terms, Symbols . . . . . . . . . . 190

7.1.1 International System and Derived Units . . . . . . . . . . . . . . 190

7.1.2 Parameters and Units at School . . . . . . . . . . . . . . . . . . . . 191

7.1.3 Terminology at School . . . . . . . . . . . . . . . . . . . . . . . . . . 193

7.2 Teaching Processes: From Everyday to Expert

and Symbol Language . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197

7.2.1 Connecting Everyday Language and

Scientific Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . 199

7.2.2 Chemical Symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202

7.2.3 Deduction of Chemical Symbols at School . . . . . . . . . . . . 207

7.3 Learner–Student Concepts of Structures and Symbols . . . . . . . . . 210

7.4 Human Element: Laymen’s Understanding

of Scientific Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215

8 Everyday Life and Chemistry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 217

8.1 Learner: Curiosity and Interest . . . . . . . . . . . . . . . . . . . . . . . . . . 218

8.2 Scientific Ideas: Chemistry Systematic Versus Everyday

Life Chemistry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222

8.2.1 Hygiene: Example “Bathroom Chemicals” . . . . . . . . . . . 223

x Contents

8.2.2 Personal Hygiene: Example “Deodorants” . . . . . . . . . . . 224

8.2.3 Health: Example “Mineral Tablets” . . . . . . . . . . . . . . . . 224

8.2.4 Nutrition: Example “Table Salt” . . . . . . . . . . . . . . . . . . 225

8.2.5 Household: Example “Baking Process” . . . . . . . . . . . . . 225

8.2.6 Habitation: Example “Fuels for Heating” . . . . . . . . . . . . 225

8.2.7 Clothing: Example “Textile Dye Remover” . . . . . . . . . . 226

8.2.8 Leisure: Example “Black and White Photography” . . . . . 226

8.2.9 Working World: Example “Metal Processing” . . . . . . . . 227

8.2.10 Electric Power Supply: Example “Accumulators” . . . . . . 227

8.2.11 House Building: Example “Hardening of Mortar” . . . . . . 228

8.2.12 Service: Example “Fire Fighting” . . . . . . . . . . . . . . . . . . 228

8.2.13 Motoring: Example “Alcohol Test” . . . . . . . . . . . . . . . . 229

8.2.14 Manufacturing: Example “Fertilizer” . . . . . . . . . . . . . . . 229

8.2.15 Air: Example “Smog” . . . . . . . . . . . . . . . . . . . . . . . . . . 230

8.2.16 Water: Example “Sterilizing Drinking Water” . . . . . . . . 230

8.2.17 Soil: Example “Soil Acidification” . . . . . . . . . . . . . . . . . 230

8.3 Teaching Processes: Systematic Chemistry Plus Everyday

Life Chemistry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231

8.4 Human Element: Role Play and Environmental Education . . . . . . 237

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 241

9 Students Discover Organic Chemistry: A Phenomena-Oriented

and Inquiry-Based Network Concept (PIN-Concept) . . . . . . . . . . . . 245

9.1 The Criteria in Relation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248

9.2 Sorting Unknown Substances with Unknown Reagents . . . . . . . 248

9.3 Interconnection of Substances by Means

of Chemical Synthesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250

9.4 Analysis of Household Substances . . . . . . . . . . . . . . . . . . . . . . 252

9.5 Discovery of Other Synthesis Relations . . . . . . . . . . . . . . . . . . . 255

9.6 Leaping to the Particle Level . . . . . . . . . . . . . . . . . . . . . . . . . . 256

9.7 Use of Formulae (“Combining Structure and Properties”) . . . . . . 260

9.8 Integration of Other Substances . . . . . . . . . . . . . . . . . . . . . . . . 262

9.8.1 Analysis of a Natural Substance . . . . . . . . . . . . . . . . . . . 262

9.8.2 Development of the Term “Homologous Series” . . . . . . . 262

9.8.3 Many Ways Lead to Acetic Acid . . . . . . . . . . . . . . . . . . 265

9.9 Other Associable Experiments and Concepts . . . . . . . . . . . . . . . 267

9.10 The PIN-Concept for Teacher Training . . . . . . . . . . . . . . . . . . . 269

9.11 The PIN-Concept for Grammar Schools . . . . . . . . . . . . . . . . . . 270

9.11.1 Evaluation by the Teachers . . . . . . . . . . . . . . . . . . . . . 271

9.11.2 Evaluation by the Students . . . . . . . . . . . . . . . . . . . . . . 271

9.11.3 Pretest Results of the Students . . . . . . . . . . . . . . . . . . . 272

9.11.4 Posttest Results of the Students . . . . . . . . . . . . . . . . . . 275

9.12 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 285

Contents xi

10 Structure-Oriented Approach in Chemical Education . . . . . . . . . . . 291

10.1 Chemical Structures in Modern Chemistry . . . . . . . . . . . . . . . . 291

10.2 Chemical Structures as the Basis for the

Interpretation of Reactions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 292

10.3 Ions on the Level of Dalton’s Atomic Model . . . . . . . . . . . . . . . 295

10.4 Atoms and Ions as Basic Particles of Matter . . . . . . . . . . . . . . . 296

10.5 Combinations of Atoms and Ions in Giant Structures

and Molecules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 298

10.5.1 Combination of Metal Atoms

(“Left and Left in Periodic Table”) . . . . . . . . . . . . . . . . 298

10.5.2 Metal Reactions: Regrouping of Metal Atoms . . . . . . . . 303

10.5.3 Combination of Ions (“Left and Right in

Periodic Table”) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307

10.5.4 Reactions of Salts: Regrouping Ions . . . . . . . . . . . . . . . 311

10.5.5 Combination of Nonmetal Atoms

(“Right and Right in Periodic Table”) . . . . . . . . . . . . . . 312

10.5.6 Reactions of Nonmetals: Regrouping of Atoms

in Molecules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 314

10.6 Summary of the Structure-oriented Approach . . . . . . . . . . . . . . 317

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 319

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 321

xii Contents

Introduction

The Russian pedagogue Itelson [1] once stated: “If engineers building bridges,

doctors treating patients and judges deciding verdicts would show such a tendency

to superficial argumentation, as it sometimes appears in pedagogy, then all bridges

would have collapsed, all patients would have died and many innocents would have

been hung alread.”.

This quotation might elicit a chuckle, but one has to admit that pedagogues’

thoroughness in preparation and argumentation in their field is not developed as

much as it is in other fields. The negative effects of mistakes in pedagogy are not as

obvious as they are in engineering, medicine or law. The professionalism of

prospective teachers should be increased and to form a basis for good lessons, the

basics of pedagogy, education and chemistry didactics have to be taught to an

adequate extent. Definitions regarding these matters should be imparted before

specific aspects of chemistry education are covered. It has to be clear, however,

that there cannot be just the one didactics! Different opinions and positions exist onthis matter: every teacher has to reflect on this in their own time and their

environment.

Pedagogy. The term derives from the word “pedagogue,” which literally means

child or boy leader in Greek. Pedagogy is a collective term for different philosophi-

cal or psychological disciplines. Their shared subject is the social action. Roth [2]

distinguishes some fields in pedagogy: “They touch the field

1. of educational research (to investigate the methodology and its practices),

2. of lessons at school (and their historical and current aspects),

3. of lessons (in its diverse determinedness as a complex interdependency)” [2].

Didactics. This term stems from the Greek philosophers’ schools of ancient

times: it derives from the word “didaskein” (Greek: to teach, to prove), or from

“didaktos” (Greek: instructive). These terms affected a lot more than just teaching

and school. In the seventeenth century Comenius was the one to connect the term

“didactics” more and more with teaching. In his “Didactica Magna” (1657) he

defined connections to current issues, everyday life and clarity as didactical

principles. For Comenius, didactics is the reasoned selection of contents for the

xiii

art of teaching (docendi artificium). Today, several didactical models are being

discussed [3–6]. Blankertz [7] and Ruprecht [8] give a summary of these models.

Aschersleben [9] defines in general: “Didactics is the universe of learning aids,

which are given to the student by the teacher or which the student uses indepen-

dently. The learning aids do not only refer to the selection of topics in education, but

also to learning methods. The lesson is the didactical situation where learning takes

place and the school is the corresponding institution. The lesson as a didactical

situation includes everything that matters to it: participants, teachers and students,

learning topics, media, learning material, and so on.” One might want to separate

didactics and methodology by having didactics answer the question of “what” and

methodology the question of “how.” The interdependency of these questions [4] as

well as the role of didactics to answer questions of “why” (question of reason) and

“what for” (question of intention), leads us to combine all these questions in the

term “didactics.” Two equivalent definitions shall be quoted:

“Didactics deals with the question of “The following questions arise:

– who – with which aims should

– what – which contents under

– when – which requirements and

– with whom – which conditions on

– where – which level with

– how – which methods in

– with what – which time with

– why and – how much success

– for what one has to learn” [10] – be taught by whom respectively

– be learned by whom?” [11]

The term “general didactics” becomes clearer, when particular forms of didac-

tics are listed and connections are being made:

– Didactics concerning type of school: elementary-, middle- and high school

didactics

– Didactics concerning groups of subjects: science, languages, social studies, and

others

– Didactics concerning specific school subjects: mathematics, biology, chemistry,

physics

Chemistry didactics deals with the aims of teaching and learning chemistry at all

different levels of schools.

Chemistry didactics. At first sight this expression might indicate that there is an

additive combination of the corresponding subject and didactical elements: chem-

istry “plus” pedagogy “plus” general didactics. At second sight it becomes clear

that a simple combination is not applicable and that it is hard to grasp all

corresponding contents. Chemistry didactics indeed concerns contents of science

on one side and contents of general didactics on the other side, but these are only

reference disciplines. Chemistry didactics as the real science for teachers is an

independent and interdisciplinary science with its own aims, tasks and methodology.

xiv Introduction

It reflects the contents of its reference disciplines and applies them to questions

concerning teaching and learning. Figure 1 illustrates Chemistry didactics as an

independent bridging discipline between pedagogy and general didactics on one

side and the sciences on the other side [12]. Figure 2 shows the interplay of

educational, scientific, and didactical parts in the first phase of teacher training

and the independent reflection in the second phase and in class, respectively [13].

To demonstrate chemistry didactics as an interdependent reflection on educa-

tional, scientific, and didactical aspects and to highlight the reasoning in chemistry

education exemplarily, an interesting experiment will be discussed as a basis

(see Fig. 3). It will be conducted in line with different didactical approaches and

analyzed accordingly.

“Iron wool on the balance.” A ball of gray shiny iron wool, which is fixed

and balanced on one side of a beam balance, is to be ignited with the Bunsen burner.

A front of red ember that moves inside of the iron wool can be observed. This side

of the balance starts to sink and finally a black product remains: iron and oxygen

have reacted to iron oxide; the additional mass of oxygen causes the observed

change. This school experiment can be carried out and analyzed in different ways –

depending on the teacher’s educational aim and on the students’ skills and abilities.

A few different possibilities are summarized in Fig. 3.

In method 1 the experiment is being demonstrated as aforementioned and

observed by the learners. The teacher has to make a decision for their explanation:

Do they offer the reaction equation in words, or do they introduce the chemical

equation with formulae, or even the redox reaction? Do they choose “exothermal”

or “DH < 0” for the energy turnover? Do they show or draw models of the

chemical structure of iron, oxygen and iron oxide? Or do they even let the students

PedagogyPhysic didactics

Physics

Chemistry

Chemistry didacticsGeneraldidactics

General didactics Didactics of sciences sciences

Biology didacticsBiology

General Pedagogy

Fig. 1 Chemistry didactics as a bridge between pedagogy/general didactics and chemistry

Introduction xv

build these models? Do they formulate an equation as a shortened model on basis

of these structural models? These questions of interpretation also arise for methods

2, 3, 4 and 5.

Inmethod 2 the ball of iron wool is weighed – either with a digital scale or with abeam scale. After igniting the wool the teacher asks the students to predict whether

the black substance will be lighter, heavier or remain at equal weight.

The teacher allows the students to hypothesize and develop solutions indepen-

dently. Because many students already have preconceptions for combustion from

their everyday life, they might predict that the product will be lighter and they will

be surprised that instead it gets heavier. A problem-oriented approach will be

possible and has the pedagogical advantage that the hypothesis “decreasing mass”

and the observation “increasing mass” cause a cognitive conflict and motivate

students to solve this problem. Curiosity and motivation to develop a solution

emerge; students are taking this problem as their own problem and want to solve it!

In method 3 the problem is stated more openly. The teacher allows the students

to discuss their experience with combustion and demonstrates the combustion

of iron wool without the scale first. The students express their concepts on this

matter – depending on ability and common practice in their class. They might

Growing expertisein teaching

Permanent reflection of teaching

Reflected teaching experience

DidacticalCompetence

ScientificCompetence

EducationalCompetence

Educationalpart of studies

General theoreticalfundamentals ofteaching andlearning processes

Application ofteaching and learningprocesses in science

General theoreticaland experimentalfundamentals ofscience

Didacticalpart of studies

Scientificpart of studies

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xvi Introduction

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Introduction xvii

spontaneously suggest comparing masses. The teacher compares the masses as a

demonstration experiment and analyzes them as described.

They might also invite the students in method 4 to plan and run such an

experiment as a student experiment. The groups of students get different equipment

and devise various solutions for the problem – depending on ideas and experimental

skills. The advantages of activity-orientation add to the advantages of problem-

orientation – another important didactical criterion.

The teachers can also introduce the topic historically-oriented in a different

method 5. They show the glowing iron wool and question the students about their

concept of the combustion process and expect the students to give the following

explanation: “something from the combustible passes over to the air”. The teacher

tells that a few centuries ago scientists thought the same and gave this “something”

the name “Phlogiston”. They can talk about Stahl’s Phlogiston theory and the

disproving of this theory by Lavoisier using scales to investigate the behavior of

mercury and mercury oxide by heating it on a stove. It is also possible that the

teacher lets students give talks on these historical developments.

Conclusion. Reflections concerning this large number of possible experiments

and interpretation alternatives of this single issue “iron wool on the balance” show

that chemistry teachers have to decide many aspects and ways to plan and to realize

lectures in chemistry. These decisions can be made and explained easier by teacher

students, when these or similar situations are familiar from the teacher training at

university. Didactical decisions have to be made constantly to initiate learning

processes and to achieve learning success especially in the beginning of chemistry

lessons[14]. Therefore the following thoughts on chemistry education apply to the

basics of chemical education at university or college.

A profound knowledge is required for the following fundamental reflections on

chemistry didactics. The publication of the German Society of Chemists (GDCh)

contains one possible listing of such scientific contents: “Memorandum on the

teacher training for chemistry lessons in classes of 10–15-year-old students” [15].

The same memorandum [15] also suggests a way of chemistry educational

training: “The aims of the didactical training of chemistry teachers are very diverse.

Not all of them can be studied in a fair amount of time and context, not even if the

part of chemistry didactics of the total volume of studies is reasonable. For this

reason, a choice of important subject areas has to be made. These subject areas can

be assigned to one of the four main areas: the learner, teaching processes, scientific

ideas and the human element.” These four levels of reflection can be found in Fig. 4

in form of concentric circles.

Every didactical subject can be divided into the four aforementioned sections:

“If the learner is in the focus of every didactical consideration, a bow can be drawn

to the human element, which influences the learner as an individual and as a

member of our society. The scientific ideas are made accessible to the learner

through teaching processes. Considering the interdependence of didactical

questions and content-related aspects, learner, teaching processes, scientific ideas

and the human element are not assigned firmly to every subject area – in fact

the sections within the concentric circles are mostly interchangeable. Therefore

xviii Introduction

the concentric rings can also be understood as ‘rotating rings’ with alternate

assignments of contents” [15].

The pie chart in Fig. 4 illustrates eight topics exemplarily, that are particularly

suitable for a chemistry educational reflection: the classical topics like experiments,structural and mental models, terminology, symbols and formulae are hatched to

show that they are assigned to the area of “scientific ideas.” Modern topics of

chemistry didactics are “learners ideas and misconceptions” (assigned to the area

“Learner”) and everyday-life chemistry (assigned to the area “human element”).

The topics that are assigned to the area “teaching processes” are teaching aims,motivation and media, which are relevant for every school subject.

The pie chart includes empty segments without topics: these reflect the fact that

there are a lot more topics for a chemistry educational consideration that could be

added to the chart. To name a few: performance assessment, role of the teacher,

curriculum development, classroom teaching research, history of chemical educa-

tion. The combination with other standard references of chemistry education

[16–24] is possible and highly recommended, due to the conceptual openness of

this book. It begins with “Learners ideas and misconceptions” because students

have preconceptions of substances and their chemical changes from everyday life

that already exist long before chemistry lessons start.

Fig. 4 Main considerations for lectures in chemistry didactics arranged in a “pie chart” [15]

Introduction xix

References

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[2] Roth, L.: Handlexikon zur Erziehungswissenschaft. M€unchen 1976

[3] Klafki, W.: Didaktische Analyse als Kern der Unterrichtsvorbereitung.

Hannover 1969

[4] Heimann, P., Otto, G., Schulz, W.: Unterricht – Analyse und Planung.

Hannover 1970

[5] Cube, F.: Kybernetische Grundlagen des Lernens und Lehrens. Stuttgart 1968

[6] Winkel, R.: Die kritisch-kommunikative Didaktik. West. P€ad. Beitr. 1 (1980),

202

[7] Blankertz, B.: Theorien und Modelle der Didaktik. M€unchen 1973

[8] Ruprecht, H.: Modelle grundlegender didaktischer Theorien. Hannover 1972

[9] Aschersleben, K.: Didaktik. Stuttgart 1983

[10] Jank, W., Meyer, H.: Didaktische Modelle. Frankfurt 1991

[11] Vossen, H.: Kompendium Didaktik der Chemie. M€unchen 1979

[12] Riedel, W., Trommer, G.: Didaktik der Okologie. K€oln 1981

[13] Hammer, H.O.: Fachdidaktik der Chemie an der Hochschule. CU 12 (1981), 5

[14] Scheible, A.: Gedanken zum Einf€uhrungsunterricht in die Chemie. MNU 19

(1966), 1

[15] Barke, H.-D., Bitterling, D., Gramm, A., Hammer, H.O., Hermanns, R.,

Leibold, R., Lindemann, H., Wambach, H.: Denkschrift zur Lehrerbildung

f€ur den Chemieunterricht in den Altersstufen der Zehn- bis F€unfzehnj€ahrigen.GDCh, Frankfurt 1983

[16] Schmidt, H.J.: Fachdidaktische Grundlagen des Chemieunterrichts.

Braunschweig 1981

[17] Christen, H.R.: Chemieunterricht. Eine praxisorientierte Didaktik. Basel,

Boston, Berlin 1990

[18] Becker, H.J., Gl€ockner, W., Hoffmann, F., J€ungel, G.: Fachdidaktik Chemie.

K€oln 1992

[19] Pfeifer, P., H€ausler, K., Lutz, B.: Konkrete Fachdidaktik Chemie. M€unchen1992

[20] Harsch, G., Heimann, R.: Didaktik der Organischen Chemie. Vom Ordnen der

Ph€anomene zum vernetzten Denken. Braunschweig 1998

[21] Lindemann, H.: Einf€uhrung in die Didaktik der Chemie. D€usseldorf 1999[22] Barke, H.-D., Harsch, G.: Chemiedidaktik Heute. Lernprozesse in Theorie

und Praxis. Heidelberg 2001

[23] Rossa, E.: Chemie-Didaktik. Praxishandbuch f€ur die Sekundarstufe I und II.

Berlin 2005

[24] Anton, M.A.: Kompendium Chemiedidaktik. Bad Heilbrunn 2008

xx Introduction