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1
Hans-Dieter Barke (Prof.Dr.)
Accompanying volume to: Misconceptions in Chemistry. Adressing Perceptions in Chemical
Education
2008
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Concept Cartoons as a Strategy in Teaching
and Learning Chemistry Accompanying volume to- Chemistry Misconceptions: Strategies for Teaching and Learning
Hans-Dieter Barke
Temechegn Engida
Sileshi Yitbarek
2008
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Contents
1. Background -----------------------------------------------------
2. Basic Chemistry Concepts-----------------------------------
2.1 Substances and Properties
2.2 Particle Concept
2.3 Structure-Property Relationships
2.4 Chemical Equilibrium
2.5 Acid-base Reactions
2.6 Redox Reactions
2.7 Complex Reactions
2.8 Energy
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Acknowledgement
We are profoundly greatfull to all school directors, teachers and students for the valuable and
unreserved support and cooperation they provided us during data collection, with out which
our task couldn’t have been accomplished.
We are greatly indebted to Artist Mulugeta Gebrekidan, Dr. Garry Knamiller, Dr. Hilde Wirbs,
Mrs. Serkalem Girma, Prof. Dr. Guenthen Harsch, Prof. Dr. Dieter Sauermann, Prof. Dr.
Rebekka Heimann, Mr. Reinhard Rölleke, and Ato Belina Terfasa for their loving
encouragement sustained through out.
Thank you all!
Barke, Temechegn & Sileshi
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Background
Concept cartoons are cartoon-style drawings that put forward alternative conceptions (a range of
viewpoints or misconceptions) about the science involved. By offering new ways of looking at
the situation they make it problematic and provide a stimulus for developing ideas further.
Concept cartoons provoke discussion and stimulate scientific thinking. (Naylor, S. and Keogh,
B. 2000).
A typical Concept cartoon has the following features: Visual representation of scientific ideas,
minimal text-in dialogue form, and alternative conceptions in equal status
This volume presents eight concept cartoons which are the results of research on the alternative
conceptions. It is designed to accompany the book entitled “Chemical Misconceptions:
Strategies for Teaching and Learning”*. The concepts are namely: Substances and Properties,
Particle Concept, Structure-Property Relationships, Chemical Equilibrium, Acid-base
Reactions, Redox Reactions, Complex Reactions and Energy.
The purpose of relying this volume on research of the alternative conceptions (misconceptions)
is to ensure that the alternatives presented are plausible, so that learners will usually identify
directly with some of the alternatives in the concept cartoons. Although many students and
teachers find such kind of research on alternative conceptions fascinating it is not always easy
to see how it can be used in the classroom. Now we strongly believe that as a strategy of
diffusion and use of the research finding the concept cartoons are very valuable and have a
profound effect on the quality of teaching, learning and assessment in chemistry education.
The organization of a typical lesson using a concept cartoon might be (Naylor, S. and Keogh,
B. 2000).:
Introduce the topic
Provide a concept cartoon to focus on a particular situation
Request a brief period of individual reflection,
Encourage small group discussion and invite groups to see if they can reach consensus
Some brief feedback to see what range of views is present - perhaps a class vote on the
alternatives
Discussion of how we could investigate the situation to find out which alternative(s) is
most acceptable
Small group enquiry
Share outcomes of enquiry
Whole class discussion, including which alternative(s) seems most acceptable now, why
other alternatives seem less acceptable and what further information we might need to be
sure
Consider how relevant theory applies to the situation
Draw ideas together and provide an explicit summary of the initial problem, the enquiry,
the outcome and what has been learnt from the enquiry
* Barke, AL Hazari, and Sileshi. 2008. Chemical Misconceptions: Strategies for Teaching and
Learning. Springer-verlag Berlin Heidenberg.
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Chemical Concepts 1. Substances and Properties
1.1 Concepts of Miscibility for Compounds
i. Evaporation of Water
Assume a beaker of pure water has been evaporated completely in a closed container. What is
the composition of the vapor?
What do you think? ____________________________________________________________________________
Water, hydrogen
and oxygen
Air
Water
Oxygen gas
and hydrogen
gas
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ii. Evaporation of Water (Pictorial)
The circle on the right of picture-1 shows a magnified view of a very small portion
of liquid water in a closed container. What would the magnified view on the right of
picture-2 show after the water evaporates?
Picture-1 Picture-2
What do you think? ____________________________________________________________________________
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1.2 Concepts of Dissolution
What is the mass of the solution when 1 kilogram of salt is dissolved in 20 kilograms of
water?
What do you think? ____________________________________________________________________________
20 kg
More than 21 kg
21 kg
19 kg
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1.3 Concepts of Rusting Iron combines with oxygen and water from the air to form rust. If an iron
nail were allowed to rust completely, one should find that the rust weighs:
What do you think?
____________________________________________________________________________
The same
as the nail
it came
from.
More than the
nail it came from
It is impossible
to predict
Less than
the nail it
came from
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1.4 Concept of destruction
A match burns in a closed container. Some matter is destroyed.
Is this what really happens ?
What do you think?
____________________________________________________________________________
No
Yes of course
It is impossible
to predict.
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1.5 Concepts of “Gases are not Substances”
A 1.0-gram sample of solid iodine is placed in a tube and the tube is closed after all of the air is
removed. The total weight of the tube and the solid iodine is 27.0 grams.
The tube is then heated until all of the iodine evaporates and the tube is filled with iodine gas.
What will be the total weight after heating?
What do you think? ____________________________________________________________________________
More than 28.0
grams
Less than
26.0 grams
26.0 grams
27.0 grams
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2. Particle concept 2.1 Macro versus Micro
What would be the properties of single atom of copper
obtained from a copper wire?
What do you think? ____________________________________________________________________________
Malleable
Has Reddish
Color
Combines with
oxygen to form
Cupric Oxide
Conduct
Electricity
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2.2 Continuous Vs Discrete views
What would ultimately be found if you divide and subdivide a drop of water in to
smaller and smaller parts, with out destroying the water itself?
What do you think? ____________________________________________________________________________
it will disappear
a drop of water is
so small that it
can’t be divided
it will disappear
Can be reached
at a point where
division is
impossible
it can be divided
with out limit
(indefinitely)
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2.3 Nature of matter Inventory
Draw a liquid after the solid melts and draw a gas after the liquid boils,
on the concept cartons.
Melts Boils
Solid Liquid Gas
Assess your Conceptual Drawing using the criteria provided under:
Criteria of Assessment for the 'Nature of Matter Inventory'
Criteria Liquid Gas
1 Conservation of particles
2 Proximity of particles
3 Orderliness of Particle arrangement
4 Location of particles in container
5 Constancy of particle size and shape
Self reflection:
__________________________
__________________________
_____________
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3. Structure-Property Relationships
How particles are combined in solid sodium chloride, NaCl ?
What do you think ? __________________________________________________________________________
electron pair in Na-Cl
molecules
Na+Cl-
ionic lattice
Na e- Cl
transfer of one
electron
Na+Cl- pairs
by electric forces
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4. Equilibrium
What is valid for chemical equilibrium?
What do you think? ___________________________________________________________________________
concentrations of all
species are equal
rates of forward and
reverse reactions are
constant
concentration of
reactants equals
concentration of
products
amounts of all
substances are the
same
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5. Acid-base reactions
What species are present in hydrochloric acid ?
What do you think?
____________________________________________________________________________
H+Cl -
particles
H+(aq) ions
and Cl - (aq) ions
HCl
molecules
and H2O
molecules
HCl (aq)
particles
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6. Redox reactions
What is the reason that an iron nail
turns red-brown in a solution of copper sulfate ?
What do you think?
__________________________________________________________________________
copper sulfate is
reduced and
copper sticks on
the nail
Cu2+ions are
reduced to
Cuatoms, copper
is formed
iron is a
magnetic
metal
copper is leaving
the sulfate and
precipitates on
the nail
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7. Complex reaction
What particles are present in a blue solution
of copper sulfate pentahydrate (CuSO4.5 H2O)?
What do you think ? __________________________________________________________________________
[Cu(H2O)6]2+(aq)
SO42-(aq)
CuSO4(aq)
H2O H2O
[CuSO4]
H2O H2O
H2O
Cu2+(aq)
SO42-(aq)
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8. Energy
Coal is burning and red glowing. Where the energy is coming from?
____________________________________________________________________________
What do you think?
____________________________________________________________________________
Coal changes
into energy;
ashes remain
Burning coal is
an exothermic
reaction,
releasing
energy
Burning coal
means mass is
decreasing and
energy is increasing
C atoms are
reacting to
energy
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Fuel is evaporating in the car engine, the mixture with air explodes and
moves the cylinder of the engine. Where the energy is coming from?
__________________________________________________________________________
What do you think ?
____________________________________________________________________________
Fuel react with
oxygen of the air,
energy is released
fuel molecules
disappear and change
directly into energy
Fuel molecules explode
in the heat of the cylinder
releasing energy
Fuel molecules are
releasing H atoms,
oxy-hydrogen gas
explodes
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References:
1. Naylor, S. and Keogh, B. 2000.Concept Cartoons: In Science Education. Great Britain by
Millgate House Publishers.
2. Barke, H.-D.2006. Chemie didaktiks: Diagnose und Korrekture von Schülervorstellungen.
Springer-verlag Berlin Heidenberg.
3. Barke, Al Hazari, Sileshi 2008. Chemistry Misconceptions: Strategies for teaching and
learning. Springer-verlag Berlin Heidenberg.
4. Sileshi Y. 2004.Traditional Vs Conceptual Questions in Chemistry: Is There a Difference?
Paper presented to the Chemical Society of Ethiopia.
5. Sileshi Y. and Temechegn E. 2003. Alternative Conceptions of Eight Chemical Concepts of
General Secondary and Preparatory Students of Addis Ababa. AAU-MA thesis.
6. Temechegn E. 2002. Students alternative Conceptions in Chemistry: Challenging the
Challenge. Solutions-a Biannual Newsletter of the Chemical Society of Ethiopia.Vol.10,
No1&2
7. Temechegn E.2001. Issues, Methods and Materials in Teaching Primary School Subjects.
AAU-Department of Curriculum and Instruction.
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