The ChemCollective Virtual Lab and Other Online
Materials
David Yaron, Michael Karabinos, Jordi Cuadros,
Emma Rehm, William McCue, David H. Dennis,
Donovan Lange, Rea Freeland
Department of Chemistry, Carnegie Mellon University
Gaea Leinhardt, Karen Evans
Learning Research and Development Center, University of Pittsburgh
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
The ChemCollective
• Build community around a specific educational goal
– Digital Libraries can combine expertise through remote and
asynchronous collaboration
– Digital Libraries can support an iterative development
process
• Ways to participate
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Use activities and give feedback
Participate in assessment studies
Modify and create activities
Discussions around activities and topics
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Outline
• New modes of practice
– Virtual labs
– Scenario based learning
• Alignment: What should we teach?
– Whole curriculum: High school chemistry
– Within topics: University chemistry
• Online support for problem solving
• Assessment of ChemCollective activities
• Pittsburgh Science of Learning Center (PSLC)
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Learning challenges and interventions
• Promoting flexibility and applicability
– From mathematical procedures to chemical phenomena
(use in chemistry)
• Virtual laboratory
– From chemical phenomena to real world
(transfer to real world)
• Scenario based learning
• Promoting coherence
– “Big picture” of chemistry
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Use in chemistry: Virtual laboratory
• Flexible simulation of
aqueous chemistry
• New mode of
interaction with
chemical concepts
• Ability to “see” inside
a solution removes
one level of indirection
in chemical problem
solving
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
How is the virtual lab used?
• Delivery
– From www.chemcollective.org
– From CD-ROM
– Install on your local computer system
• Classroom uses
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During recitation
As take-home work
Pre- and post-labs
Lab make-ups
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
A survey of Virtual lab problems
• 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
• Puzzle problems (open-ended and inquiry based experiments)
– Layered problems
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Predict and Check
Students use the virtual lab to check the results of a penciland-paper calculation or qualitative prediction
• Potential benefits
– Encourages students to see connection between
calculations/qualitative predictions and an experimental
procedure
– Observations indicate that the shift from paper and pencil to
lab activity can challenge students
– Students can make use of intermediate results in locating
errors
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Predict and Check
• Traditional calculation
Thermochemistry/Coffee: Calculate the amount of 100C milk that must
be added to 250ml of 95oC coffee to lower its temperature to 90oC.
Check your answer in the virtual lab.
• As part of design activity
Thermochemistry/Camping 3: Using the virtual lab, create two
solutions, initially at 25°C, that, when mixed together in equal
volumes, cause the temperature of the mixture to increase from
25°C to 60°C
Can be done as predict and check, but is often done in
iterative process with some predict and check steps
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Virtual Experiments
Students generate and interpret data in the chemistry virtual lab
program
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
Thermochemistry/Camping 1:
“Construct an experiment to
measure the heat of reaction
between A and B?”
• Students who could perform the textbook procedure had difficulty
designing the experiment, and needed help from a human tutor.
– The procedure is not triggered in response to relevant prompt
– The Virtual Lab format requires students to beyond a strategy of matching
words to equations
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Puzzle Problems
Stoichiometry/Oracle 1 and 2: Given four substances A, B, C,
and D that are known to react in some weird and
mysterious way (an oracle relayed this information to you
within a dream), design and perform virtual lab
experiments to determine the reaction between these
substances, including the stoichiometric coefficients. You
will find 1.00M solutions of each of these chemical
reagents in the stockroom.
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Oracle Problem Observations
• Intent was to give practice with determining reaction coefficients
A + 2B  3C + D
• Observation
When A is mixed with B, some A remains
so the reaction must be:
A+BC+D+A
Reveals misunderstanding of limiting reagent concept (even though they
could easily perform textbook limiting reagent problems)
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Layered Problems
• A set of activities involving the same chemical system, but
modeling the system with varying levels of complexity and
approximation.
• The approximations can either be removed or invoked
• Encourage students to reflect on relations between different
problem types
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Layered Problems
• Acid Mine Drainage Scenario treats river at three
levels
– As distilled water at room temperature
– As distilled water with seasonally-varying temperature
– As a buffered solution
• For all three models, student discuss factors
influencing amount of Fe precipitated in the river bed
• See http://www.chemcollective.org/AMD/
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Authoring a virtual lab activity
• Add chemical species and reactions (if desired)
– Can create “fictional” proteins, drugs etc.
• Create Stockroom Solutions
• Specify available functionality
– Viewers
• For example, turn off “Solution Contents” for exercises involving
unknowns
– Transfer mode
• Precise vs. realistic
• HTML problem description can be included
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Transfer to real world: Scenarios
• Scenario based learning
– Embed the procedural knowledge of the course in a scenario that
highlights its utility
– Scenarios that touch down at various points in the course may
promote coherence
• Motivated a study of alignment between:
– What we teach in high school chemistry
– What informed citizens need to know about chemistry
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Traditional course structure
• CA state standards
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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
Chemistry AP exam guide’s are similarly structured around chemistry topic list
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Domain analysis
• Evidence of the domain as practiced
– Nobel prizes for past 50 years
– NY Times Science Times for 2002
– Scientific American News Bites for 2002
• Evidence of the domain as taught
– CA state content standards
– Best selling textbooks
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Domain map: The big picture
EXPLAIN
ANALYZE
Hypothesis
Generation
Goal
Functional
Motifs
(What do you
want to know?)
Hypothesis
Testing
Process
Representational
Systems
The Chemistry Collective
SYNTHESIZE
(How to determine
what you have)
Structural
Motifs
TOOLBOX
Assembly
Motifs
Quantification
Systems
http://www.chemcollective.org
Duke 2005
Comparison
• Domain as practiced
– Scientific literature spread equally between these three
subdomains
• Domain as taught
– Textbooks and standards found only in Toolbox and Analyze
subdomain
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
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
New
Elements
Quantitative
Analysis
Properties of
Gasses
Energy
(How much do you have)
Properties of
Matter
Hypothesis
Generation
Atomic Structure
(What do you
want to know?)
Stoichiometery
(Frameworks an expert
sifts through to construct
an explanation)
Functional
Motifs
Acids and Bases
in Solution
Non-Biological
Microscopy
Techniques
Properties of
Solutions
Properties of
Atoms and
Molecules
Pharmaceuticals
Food and Health
Radioactive
Dating
What is a Metal,
Crystal, Salt?
Electromagnetism
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
Ionic / Alloys
Extraction
Scavenge O2
Hypothesis
Testing
Selectively shut
down pathways
Chromatography
Separation
Block a
functional group
TOOLBOX
Formulation
Structure
Reactions
Molecular
Structure
Atomic Structure
Orbitals
Configuration
The Chemistry Collective
Lewis Dot
Filtration
Quantification
Systems
Representational
Systems
Nomenclature
Paper
TLC
Gas
Column
HPLC
Distillation
Correlate
Observables
Hold one thing
fixed while
changing
another
Van der Waals /
Electrostatic
Biological
Engineering
Process
Motifs
Filtration
Radio Label
Transition Metal
Complexes
(Metal Ligand)
Format
Units
Mole
Molarity
Partial Pressure
Stoichiometery
VSEPR
http://www.chemcollective.org
Duke 2005
Domain map as basis for course design
• Guide development of scenarios
– Ensure distribution at both upper and lower levels
• Mediate conversation between traditional and
reformed course
– Encourage students to reflect on how the course concepts
fit into chemistry as a domain
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
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)
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Stoichiometry review course
• As in Bangladesh groundwater
– Measurement of As
concentration
– Remediation
– Challenges facing modern
analytical chemistry
• http://www.cmu.edu/oli
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Mixed Reception
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Middle school through high school: Big Concepts
• Structure
– Relation to properties
• Functional groups
• Emergent properties (bonding pattern  molecular interactions - 3 d
structure)
• Transformation
– Physical transformations and chemical reactions
• Energy and motion
– Heat
– Molecular motion
• Organizing materials: water, gold and plastic
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Within topic alignment: Acid base chemistry
• Traditional textbook
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Definition of pH
Strong acids
Weak acid dissociation equilibrium: calculate pH of a weak acid
Titrations
Buffers
• Use in later courses (organic chemistry, biology)
– Big idea: Will a labile proton be present on a molecule?
• Compare pH to pKa
– Use a buffer to control pH, so you can control the “big idea”
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Support for problem solving
• Based on hourglass view of problem solving
Initial problem analysis
and selection of procedure
Implementation of computation
or procedure
Structured dialogues,
reflective prompts
Templated feedback,
pseudotutors
Reflection on problem
solving efforts
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Templated feedback
Analysis of student response for common error types hints
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Pseudotutors
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Fading
Path 3
S
Determine
target PH
Determine
target [A-]/[HA]
Path 2
Path 1
Construct
solution
with target
[A-]/[HA]
F
Determine solutions
and volumes mixed.
Schematic representation of scaffolding for design of a buffer solution.
Ovals represent episodes (pseudotutors or templated feedback).
Support is added/faded by switching paths.
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Support for problem solving
• Based on hourglass view of problem solving
Initial problem analysis
and selection of procedure
Implementation of computation
or procedure
Structured dialogues,
reflective prompts
Pseudotutors,
templated feedback
Reflection on problem
solving efforts
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Problem analysis
• Current approach leaves this as “implicit knowledge”
• Structured dialogue for heat exchange
– What is the source of the heat?
• How do you describe that effect: (q=m Cv DT, q=n DH, ..)
– What is the drain of the heat?
• How do you describe that effect: (q=m Cv DT, q=n DH, ..)
• Observations on heat exchange
– Most students have difficulty with above questions if heat is
coming form a chemical reaction.
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Implicit knowedge in equilibrium and acid-base chemistry
• General strategy
– Determine majority species first
– Then determine minority species
• Key skill for which students do not get sufficient practice
– Given a solution (1 M HCl, 0.5M NaOCH3), what are the majority
and minority species.
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Results from other domains
• Geometry
– Sub-goal structure of proofs was implicit knowledge (Anderson,
Koedinger, Greeno..)
• Statistics
– Students could carry out statistical analysis procedures, but could
not select appropriate procedures (Lovett)
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Student opinion data
• Student surveys (data is % response)
Not helpful
helpful
Lectures
0
10
33
40
Reading
8
34
25
10
Textbook problems
10
33
25
7
Graded HW
5
7
34
37
Vlab
10
18
28
25
Recitation
2
16
30
34
– Attitude towards virtual lab correlates strongly with confidence measures
(R2=0.82)
– Confidence does not correlate to performance (R2=0.01)
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Assessment
• Study at Carnegie Mellon
– Second semester intro course, 150 students
• Information used
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Pretest
9 homework activities
3 hour exams
2 pop exams (practice exam given 5 days before hour exam)
Final exam
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Correlations
Pre
Test
Pre
test
Home-work Pop Exam
Exam
Final
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
The Chemistry Collective
http://www.chemcollective.org
1.00
Duke 2005
Structural equation model
PT
PEX3
PEX2
EX2
C-ACH
EX1
H1
The Chemistry Collective
H2
http://www.chemcollective.org
H3
Duke 2005
Pittsburgh Science of Learning Center (PSLC)
• Chemistry is one of seven domain “Learnlabs”
– Bring learning scientists and educators together to perform well
controlled studies in real classrooms
• Questions of interest to the chemistry Learnlab
– What is the best balance of worked examples and problem
solving?
– Relative benefits and dangers of virtual vs. real labs?
– Relative benefits of explicit instruction versus discovery,
especially of strategies?
• Actively soliciting instructors for studies in 2006
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Thanks To
Carnegie Mellon
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Michael Karabinos
William McCue
David H. Dennis
Jodi Davenport
Donovan Lange
D. Jeff Milton
Jordi Cuadros
Rea Freeland
Emma Rehm
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Tim Palucka
Jef Guarent
Amani Ahmed
Giancarlo Dozzi
Katie Chang
The Chemistry Collective
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Erin Fried
Jason Chalecki
Greg Hamlin
Brendt Thomas
Stephen Ulrich
Jason McKesson
Aaron Rockoff
Jon Sung
Jean Vettel
Rohith Ashok
Joshua Horan
Funding
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NSF: CCLI, NSDL, SLC
William and Flora Hewlett
Foundation
Howard Hughes Medical
Institute
Dreyfus Foundation
LRDC, University of Pittsburgh
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Gaea Leinhardt
Karen Evans
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Baohui Zhang
http://www.chemcollective.org
Duke 2005
Stoichiometry review course
• Basic tools of stoichiometry
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Significant figures
Unit conversions, including Avogadro’s number
Molecular weight/ molar mass
Composition stoichiometry
Solution concentration
• Empirical formula
• Reaction stoichiometry
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Stoichiometric conversion and percent yield
Limiting reagents
Titration
Analysis of mixtures
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Pseudotutors
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Fictitious chemicals
• Protein-drug binding
– Add 3 species: Protein, Drug, Protein:Drug
– Add reaction: Protein + Drug  Protein:Drug
• Thermodynamic properties
Protein + Drug  Protein:Drug
DHfo
0
0
DH
S0
0
0
DS
Determine DH and DS from K at two different temperatures
The Chemistry Collective
http://www.chemcollective.org
Duke 2005
Fictitious chemicals
• Add a new acid
– Add 2 species: HA, A– Add reaction: HA  H+ + A-
• Thermodynamic properties
HA 
H+
+
ADHfo
DH (H+)
DH (H+)
DH
S0
So (H+)
So (H+)
DS
Determine DH and DS from K at two different temperatures
• We also have a “Chemical Database Management System”
that will generate thermodynamic data from a list of K’s etc.
The Chemistry Collective
http://www.chemcollective.org
Duke 2005