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 – – – – 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 – – – – 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 – – – – 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+BC+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 – – – – – – – – – – – • 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 • • • • • 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 – – – – – 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 – – – – – 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 • • • • • • • • • Michael Karabinos William McCue David H. Dennis Jodi Davenport Donovan Lange D. Jeff Milton Jordi Cuadros Rea Freeland Emma Rehm • • • • • Tim Palucka Jef Guarent Amani Ahmed Giancarlo Dozzi Katie Chang The Chemistry Collective • • • • • • • • • • • 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 Karen Evans • Baohui Zhang http://www.chemcollective.org Duke 2005 Stoichiometry review course • Basic tools of stoichiometry – – – – – Significant figures Unit conversions, including Avogadro’s number Molecular weight/ molar mass Composition stoichiometry Solution concentration • Empirical formula • Reaction stoichiometry – – – – 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