What is conceptual learning in chemistry
and why should we promote it?
David Yaron+, Michael Karabinos+, Jodi Davenport*, Jordi Cuadros+
Department of Chemistry+ and Psychology*, Carnegie Mellon University
Gaea Leinhardt, Jim Greeno, Karen Evans
Learning Research and Development Center, University of Pittsburgh
Laura Bartolo+, John Portman*
Department of Information Science+ and Biology*, Kent State University
W. Craig Carter, and Donald Sadoway
Department of Materials Science, MIT
CMU 2009
http://www.chemcollective.org
1
Digital Library and Projects Overview
Materials for Introductory chemistry
NSDL
Virtual labs
Scenario based learning
Tutorials
Chem Ed DL
Portal for all of chemistry
Collaboration between
ACS and J.learning
Chem. in
Ed.
ChemDL
Can OLI
a digitalMatDL
library provide a community
space for promotingPSLC
conceptual
Fullchemistry?
online courses
Fundamental studies
www.chemeddl.org
to
advance the theory of learning
www.cmu.edu/oli
ChemCollective
Open Learning Initiative
OLI
CMU 2009
www.learnlab.org
www.chemcollective.org
Pittsburgh Science
of Learning Center
PSLC
http://www.chemcollective.org
2
ChemCollective as a Digital Library
ChemCollective
Learning
Technologist
Educators
Configurable virtual lab
Tools for creating
explanations and
assessments
Activity and curriculum
creation
Learning
Scientists
Domain analysis
Learning assessment
Feedback on
classroom use
Tools for data collection
CMU 2009
http://www.chemcollective.org
3
What is conceptual learning?
• Physics’ Force Concept Inventory
– Mathematical problem solving does not necessarily lead to ability
to answer qualitative questions
– Students learn what they practice.
• Physics’ answer to “What is conceptual learning?”
– Non-conceptual instruction
students struggle with hard problems
– Conceptual instruction
Couple mathematical problem solving with qualitative questions
CMU 2009
http://www.chemcollective.org
4
Conceptual learning
• Being systematic about the goals of instruction and aligning
the instruction to these goals
• Four projects related to conceptual learning
–
–
–
–
Virtual lab
What is needed for scientific literacy?
Teaching chemical equilibrium
Molecular science across disciplines
CMU 2009
http://www.chemcollective.org
5
Virtual laboratory
• Goal: Connecting
mathematics to
authentic chemistry
• Approach: Problem
solving that involves
experimental design
and data analysis
• Virtual Lab: Ability to “see” inside a solution removes one level of
indirection in chemical problem solving
CMU 2009
http://www.chemcollective.org
6
Classroom uses
• In a computer lab
• As take-home work
• Pre- and post-labs
• Lab make-ups
• Supplement to in-class demonstrations
• Current topic list
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–
–
–
Molarity
Quantitative analysis
Solubility
Acids and bases
- Stoichiometry
- Chemical equilibrium
- Thermochemistry
• Problem types
– Predict and check
– Virtual experiment
• Labs designed to be similar to common physical labs
• Puzzle problems (open-ended and inquiry based experiments)
CMU 2009
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7
Virtual lab use
• Replacing textbook-style problems with experimental design and
data analysis problems
Typical textbook problem
“When 10ml of 1M A was mixed
with 10ml of 1M B, the
temperature went up by 10
degrees. What is the heat of the
reaction between A and B?”
Virtual Lab problem
“Construct an experiment to
measure the heat of reaction
between A and B?”
• Breaks shallow “means-ends” problem solving strategy
– 4 sections of 30-45 students working alone; 4-5 instructors/observers
– The Virtual Lab format requires students to go beyond matching words to
equations
CMU 2009
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8
Virtual lab use
“The virtual lab contains 1M solutions of A, B, C, and D. Construct
experiments to determine the reaction between these reagents”
100 mL 1 M A + 100 mL 1 M C  0.25 M A + 0.25 M B + 0.25 M D
• 50 % of students put A as reactant and product
A+CA+B+D
• Actual reaction
A+2CB+D
CMU 2009
http://www.chemcollective.org
9
Virtual lab use
“The virtual lab contains 1M solutions of A, B, C, and D. Construct
experiments to determine the reaction between these reagents”
100 mL 1 M A + 100 mL 1 M C  0.25 M A + 0.25 M B + 0.25 M D
• Find stoichiometry through titration
– Slowly add 1M A to 100 ml of C until all the C is consumed
– 50 mL of A leads to 1:2 ratio of A to C in the reaction
A+2C
CMU 2009
http://www.chemcollective.org
10
Virtual lab use
“The virtual lab contains 1M solutions of A, B, C, and D. Construct
experiments to determine the reaction between these reagents”
Single step solution
– Mix equal volumes of 1M A, 1M B, 1M C, and 1M
A
B
C
D
Initial
0.25
0.25
0.25
0.25
Change
-0.125
+0.125
-0.25
+0.125
Final
0.125
0.375
0
0.375
A+2C  B+D
CMU 2009
http://www.chemcollective.org
11
Assessment within a large lecture course
• Study at Carnegie Mellon
– Second semester intro course, 150 students
• Information used
–
–
–
–
–
Pretest
9 homework activities (virtual labs with templated feedback)
3 hour exams
2 pop exams (practice exam given 5 days before hour exam)
Final exam
CMU 2009
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Correlations
Pre
Test
Pre
test
Home-work Pop Exam
Exam
1.00
Home work 0.03
1.00
Pop
Exam
0.50
0.15
1.00
Exam
0.32
0.43
0.51
1.00
Final
0.23
0.58
0.37
0.59
CMU 2009
Final
http://www.chemcollective.org
1.00
13
Regression and structural equation model
•
•
•
Linear regression accounts for 48% of the variance in the final grades
Influence of homework accounts for half of the model predictions
Structural equation model supports conclusions drawn from the regression
CMU 2009
http://www.chemcollective.org
14
Assessment within OLI online stoichiometry module
• Study design
– Treatment (20): Online course
including a scenario, tutors and
virtual lab homework
– Control (20): Paper and pencil,
worked examples and practice
– Assessment was traditional
problem solving of quantitative
stoichiometry problems, and
some qualitative questions
Text-only
Multimedia
Virtual
Lab use was positively
correlated
Mean=77
with Mean=65
better performance.
CMU 2009
http://www.chemcollective.org
15
Conceptual learning in chemistry: What is it?
• Virtual laboratory
– Connecting mathematics to authentic chemistry
• What is needed for scientific literacy?
• Teaching chemical equilibrium
• Molecular science across disciplines
CMU 2009
http://www.chemcollective.org
16
Conceptual learning in chemistry: What is it?
• Virtual laboratory
– Connecting mathematics to authentic chemistry
• What is needed for scientific literacy?
• Teaching chemical equilibrium
• Molecular science across disciplines
CMU 2009
http://www.chemcollective.org
17
Traditional high school course structure
• CA state standards
–
–
–
–
–
–
–
–
–
–
–
•
Standard 1 Atomic and Molecular Structure
Standard 2 Chemical Bonds
Standard 3 Conservation of Matter and Stoichiometry
Standard 4 Gases and Their Properties
Standard 5 Acids and Bases
Standard 6 Solutions
Standard 7 Chemical Thermodynamics
Standard 8 Reaction Rates
Standard 9 Chemical Equilibrium
Standard 10 Organic Chemistry and Biochemistry
Standard 11 Nuclear Processes
Current chemistry AP exam guides are similarly structured around chemistry topic list
CMU 2009
http://www.chemcollective.org
18
Domain analysis for chemical literacy
• Evidence of the domain as practiced
– Nobel prizes for past 50 years (1952-2002)
– NY Times Science Times for 2002 (54 reports)
– Scientific American News Bites for 2002 (32 reports)
• Evidence of the domain as taught
– CA state content standards
– Best selling textbooks
CMU 2009
http://www.chemcollective.org
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Domain map
EXPLAIN
ANALYZE
Goal
Hypothesis
Generation
(What do you
want to know?)
Functional
Motifs
Process
Hypothesis
Testing
(How to determine
What you have)
Structural
Motifs
TOOLBOX
Assembly
Motifs
Representational
Systems
CMU 2009
SYNTHESIZE
http://www.chemcollective.org
Quantification
Systems
20
Full domain map
Is composed of
Is composed of
EXPLAIN
Is composed of
ANALYZE
SYNTHESIZE
Radioactivity
Types of
Reactions
Catalysts
Super Molecular
Structure
Acid and Base
Periodicity
Qualitative
Analysis
Redox
Materials
Molecular Structure
(What is its Structure)
Goal
Precipitation
Hypothesis
Generation
New
Elements
Quantitative
Analysis
Properties of
Gasses
Energy
(How much do you have)
Properties of
Matter
(Frameworks an expert
sifts through to construct
an explanation)
Functional
Motifs
Atomic Structure
(What do you
want to know?)
Stoichiometery
Acids and Bases
in Solution
Radioactive
Dating
What is a Metal,
Crystal, Salt?
Electromagnetism
Non-Biological
Microscopy
Techniques
Properties of
Solutions
Properties of
Atoms and
Molecules
Pharmaceuticals
Food and Health
Polymers
Biological
Scattering
Techniques
Phases of Matter
Liquid, Solid, Gas
Structural
Motifs
Investigation
Simple
Molecules
Titration
Equilibrium
Method
Spectroscopy
(How to determine
what you have)
Thermodynamics
Heat and Energy
Molecular Crystals
UV/Vis
IR
NMR
MassSpec
3-D Networks
Metals / Alloys /
Semiconductors
Simple Organic
Covalent
Bonding
Extraction
Kinetics
Catalysis
Structure
Property
Relationships
Similar structure
as an explanation
Chromatography
Separation
Paper
TLC
Gas
Column
HPLC
Chemical
Design
Non Covalent
Bonding
Distillation
Biological
Engineering
Process
Motifs
Extraction
Scavenge O2
Hypothesis
Testing
Selectively shut
down pathways
Block a
functional group
TOOLBOX
Formulation
Structure
Reactions
Molecular
Structure
Atomic Structure
Orbitals
Configuration
Lewis Dot
Filtration
Quantification
Systems
Representational
Systems
Nomenclature
Paper
TLC
Gas
Column
HPLC
Distillation
Correlate
Observables
CMU 2009
Chromatography
Separation
Hold one thing
fixed while
changing
another
Van der Waals /
Electrostatic
Ionic / Alloys
Filtration
Radio Label
Transition Metal
Complexes
(Metal Ligand)
Format
VSEPR
Units
Mole
Molarity
Partial Pressure
Stoichiometery
Evans, Karabinos, Leinhardt & Yaron, J. Chem. Ed. (2006)
http://www.chemcollective.org
21
Results of text analysis
100%
90%
Synthesize
80%
70%
60%
Analyze
OUTSIDE
SYNTHESIZE
ANALYZE
EXPLAIN
TOOLBOX
50%
40%
Explain
30%
20%
Toolbox
10%
0%
Chem in the World
CMU 2009
Chem in Textbooks
http://www.chemcollective.org
22
Scenarios: Examples
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•
•
•
•
Mixed reception (molecular weight, stoichiometry)
Cyanine dyes binding to DNA (equilibrium, Beer’s law)
Meals read-to-eat (thermochemistry)
Mission to mars (redox, thermochemistry)
Arsenic poisoning of wells in Bangladesh (stoichiometry,
titration, analytical spectroscopy)
• Ozone destruction (kinetics)
CMU 2009
http://www.chemcollective.org
23
Conceptual learning in chemistry: What is it?
• Virtual laboratory
– Connecting mathematics to authentic chemistry
• What is needed for scientific literacy?
– Replacing skills focus with knowledge of what chemists do
• Teaching chemical equilibrium
• Molecular science across disciplines
CMU 2009
http://www.chemcollective.org
24
Conceptual learning in chemistry: What is it?
• Virtual laboratory
– Connecting mathematics to authentic chemistry
• What is needed for scientific literacy?
– Replacing skills focus with knowledge of what chemists do
• Teaching chemical equilibrium
• Molecular science across disciplines
CMU 2009
http://www.chemcollective.org
25
Chemical equilibrium
• Goal: Discovery why this topic is so difficult to learn, and try
to fix it
• Approach:
– Domain analysis
– Student talk alouds on traditional problems
– Discovered “implicit knowledge” that could be made explicit in the
instruction
CMU 2009
http://www.chemcollective.org
26
Chemical equilibrium
• Goal: Discovery why this topic is so difficult to learn, and try
to fix it
• Approach:
– Domain analysis
1. Utility of the knowledge
2. Detailed structure of the knowledge
3. Psychological aspects of the knowledge
– Student talk alouds on traditional problems
– Discovered “implicit knowledge” that could be made explicit in the
instruction
CMU 2009
http://www.chemcollective.org
27
Chemical equilibrium / Acid-base chemistry
1) Utility of the knowledge
–
How is this knowledge used in organic chemistry and molecular
biology
1) Compare pH to pKa to determine ionization state
2) Buffers used to control pH (qualitative not quantitative)
3) Titration as an analytical technique
–
Current instruction
1: Almost a footnote (in the pH indicators section)
2-3: Coverage may not be sufficiently qualitative
CMU 2009
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28
Chemical equilibrium / Acid-base chemistry
2) Detailed structure of the knowledge
– Need to be flexible with “progress of reaction”
– General strategy (majority/minority species strategy)
3) Psychological aspects of the knowledge
– LeChatlier (especially with addition/removal of a species) is most
retained concept
– Broad confusion regarding “progress of reaction”
• Q (current state) vs. K (state towards which system tends)
• Meaning of “initial” vs. “equilibrium” state
CMU 2009
http://www.chemcollective.org
29
What can we build on?
• LeChatlier’s principle plays role of “prior knowledge”
• Human respiration is scenario to which to attach “initial” vs.
“equilibrium” state
– Blood entering lungs and muscles experiences a new initial state
– Blood leaving lungs and muscles has reached a new equilibrium
state
CMU 2009
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Progress of Reaction
• Based on expert/novice protocol study
2NO2
CMU 2009
N2O4
http://www.chemcollective.org
31
Majority / Minority Problem Solving Strategy
• Old instruction
– “Small x approximation”
– Highly mathematical
• New instruction
– Majority/minority species strategy
– Couples the problem solving steps to qualitative reasoning
CMU 2009
http://www.chemcollective.org
32
Old
Instruction
Small x
approximation
CMU 2009
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33
New
Instruction
Step 1:
Push strong
reactions to
completion
(identify majority
species)
Step 2:
Use K=Q to find
[ ]’s of minority
species
CMU 2009
http://www.chemcollective.org
34
Results
• Coordination of core concepts
with problem solving
procedures led to large
improvement in problem
solving performance.
CMU 2009
http://www.chemcollective.org
35
Majority vs. minority species
• A general strategy
– Find all strong reactions (K>>1)
• Acid base: OH- + H+ ; HA + OH• Solubility: M+ + X- and M+ + L
and A- + H+
– Thought experiment: Assume large K’s are infinite and do a
limiting reagent calculation
• All species that do not go to zero, are majority species and you now know
their concentration
– Determine minority species, via equilibrium expressions (K=Q)
CMU 2009
http://www.chemcollective.org
36
Conceptual learning in chemistry: What is it?
• Virtual laboratory
– Connecting mathematics to authentic chemistry
• What is needed for scientific literacy?
– Replacing skills focus with knowledge of what chemists do
• Teaching chemical equilibrium
– Connecting problem solving procedures to chemical
concepts/mental models
• Molecular science across disciplines
CMU 2009
http://www.chemcollective.org
37
Conceptual learning in chemistry: What is it?
• Virtual laboratory
– Connecting mathematics to authentic chemistry
• What is needed for scientific literacy?
– Replacing skills focus with knowledge of what chemists do
• Teaching chemical equilibrium
– Connecting problem solving procedures to chemical
concepts/mental models
• Molecular science across disciplines
CMU 2009
http://www.chemcollective.org
38
Conceptual frameworks that cross disciplines
• Scope is molecular science
– How molecular structure and motion lead to emergent macroscopic properties
– The synthesis/engineering of structures with desirable properties
• Build materials for discipline-specific courses, but that use a common
core set of materials to show interdisciplinary connections
• Experts from multiple domains (chemistry, materials science,
biophysics) met to identify concepts/frameworks that are
– Central to their domain
– Have strong leverage
– Are difficult to teach/learn
CMU 2009
http://www.chemcollective.org
39
Outcome of the Design Process
• Reaction paths and energy landscapes
• Used to describe, for example,
– Organic chemistry reactions
– Diffusion on surfaces
– Protein folding/unfolding
CMU 2009
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40
Development process
• Analyze content with experts, novices and psychologists
• Sequential focus on aspects of the diagram
– What is Q?
– What is temperature?
– Energy vs. free energy
CMU 2009
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What is the reaction coordinate Q?
CMU 2009
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Motion connected to a heat bath
CMU 2009
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Coordination
CMU 2009
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Entropy: Energy vs. free energy
CMU 2009
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45
Other conceptual frameworks of molecular science
• Reaction paths and energy landscapes
• Molecular forces
– e.g. Structure formation at different temperatures
• Economies of exchange
– Heat, proton (acid/base) and electron (redox) exchange
• How natural and designed systems promote one chemical
process over another
– e.g. Kinetic vs. thermodynamic control
CMU 2009
http://www.chemcollective.org
46
Conceptual learning in chemistry: What is it?
• Virtual laboratory
– Connecting mathematics to authentic chemistry
• What is needed for scientific literacy?
– Replacing skills focus with knowledge of what chemists do
• Teaching chemical equilibrium
– Connecting problem solving procedures to chemical
concepts/mental model
• Molecular science across disciplines
– Conceptual frameworks that have broad utility
CMU 2009
http://www.chemcollective.org
47
Digital library assessment
• Web logs
2004
2005
2006
2007
2008
ChemCollective Website Unique Visitors
101,397
106,429
123,400
161,481
211,477
Vlab (individual users)
Access the applet to perform experiment online
Download the virtual lab to local drive
18,757
4,329
48,626
6,425
59,733
15,678
62,871
17,556
117,875
24,530
• Monitoring the pathway from seeing to contributing
–
–
–
–
Target audience: 9000 college and 100,000 high school instructors
See the collection: 7000
Use the collection: 200
Contribute to the collection: 62
• 11 have contributed activities (56 activities)
• 11 have contributed translations (11 languages, 70 activities)
• 40 have given feedback, 13 volunteered for learning studies
CMU 2009
http://www.chemcollective.org
48
Closing comments
• Can digital libraries serve as community spaces for
promoting conceptual teaching and learning of chemistry?
– Virtual lab does get reused and repurposed
• Homework tool
• Many instructors find the approach compelling
– Chemical equilibrium and cross-disciplinary materials
• Too soon to tell
– Shifting high school chemistry from skills to literacy
• No progress yet
CMU 2009
http://www.chemcollective.org
49
Thanks To
Carnegie Mellon
•
•
•
•
•
•
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•
•
Michael Karabinos
Jodi Davenport
Donovan Lange
D. Jeff Milton
Jordi Cuadros
Rea Freeland
Emma Rehm
William McCue
David H. Dennis
•
•
•
•
•
Tim Palucka
Jef Guarent
Amani Ahmed
Giancarlo Dozzi
Katie Chang
CMU 2009
•
•
•
•
•
•
•
•
•
•
•
Erin Fried
Jason Chalecki
Greg Hamlin
Brendt Thomas
Stephen Ulrich
Jason McKesson
Aaron Rockoff
Jon Sung
Jean Vettel
Rohith Ashok
Joshua Horan
Funding
•
•
•
•
NSF: CCLI, NSDL, SLC
William and Flora Hewlett
Foundation
Howard Hughes Medical
Institute
Dreyfus Foundation
LRDC, University of Pittsburgh
•
•
•
Gaea Leinhardt
Jim Greeno
Karen Evans
•
Baohui Zhang
http://www.chemcollective.org
50