Using Virtual Lab Activities for Introductory Chemistry

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Using and Authoring Virtual Lab Activities for Introductory ChemistryDavid Yaron, Michael Karabinos, Jordi Cuadros, Emma Rehm, Tim Palucka, Rea Freeland, D. Jeff Milton Department of Chemistry, Carnegie Mellon University Gaea Leinhardt, Karen Evans, Javier Alejandro Corredor Learning Research and Development Center, University of Pittsburgh

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Learning challenges and interventionsPromoting 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

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Use in chemistry: Virtual laboratoryFlexible 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

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Installing the Virtual LabWays to run the lab in your classroom From www.chemcollective.org From CD-ROM Feel free to make copies of the CD yourself, or request packs from us Install on your local computer system To install the lab from the CD Add a folder named “virtualLab” in your “My Documents” folder Drag the contents of the CD-ROM to this “virtualLab” folder Go into the virtualLab folder and click on autorun.exe

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Options for introducing the lab to your studentsDemo the lab in class Show how to pour Show information available in the viewers Show how to use the “load homework” menu item Ask students to watch the brief video demonstrating how to use the lab Ask students to do the step-by-step walkthrough A basic user guide with instructions for using each feature of the lab is also available

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A survey of Virtual lab problemsCurrent topic list Molarity - Stoichiometry Quantitative analysis - Chemical equilibrium Solubility - Thermochemistry Acids and bases Problem types Predict and check Virtual experiment Puzzle problems (open-ended and inquiry based experiments) Layered problems

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How to use in your classroomDuring recitation As take-home work Pre- and post-labs Lab make-ups Supplement to in-class demonstrations

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Predict and Check Students use the virtual lab to check the results of a pencil-and-paper calculation or qualitative prediction Potential benefits Encourages students to see connection between calculations/qualitative predictions and an experimental procedure Design of the appropriate experiment can be challenging Observations indicate that the shift from paper and pencil to lab activity can be difficult for students Students can make use of intermediate results in locating errors

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Predict and CheckTraditional 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

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Virtual ExperimentsStudents 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 prevents students from using strategy of matching words to equations See also: http://iry.chem.cmu.edu/oldlab/ for unknown acid with feedbackTypical 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 generate and interpret data in the chemistry virtual lab program

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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.

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Oracle Problem ObservationsIntent 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) This may be a good opportunity for an Elicit-Confront-Resolve instructional strategy

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Layered ProblemsA 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 as one moves through a series of problems. These interconnected layers, particularly with the addition of structured debriefing, invite students to reflect on how the removal or an addition of an assumption changes both their problem solving approach and the predicted results.

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Layered ProblemsAcid 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://iry.chem.cmu.edu/AMD/

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Authoring a virtual lab activityAdd 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: student enters exact amount to transfer Facilitates comparison with paper and pencil problems Realistic: simulates accuracy attainable in real lab Forces student to use correct apparatus (buret for titration) Significant figures transfer mode Teaches relation between experimental technique and accuracy HTML problem description can be included

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Assessing your activityBe explicit about your learning goals Design questions that test whether you have achieved your learning goal

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Fictitious chemicalsProtein-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

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Fictitious chemicalsAdd a new acid Add 2 species: HA, A- Add reaction: HA  H+ + A- Thermodynamic properties HA  H+ + A- DHfo 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.

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Transfer to real world: ScenariosScenario 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 Outcome of design process Attempt to organize scenario development led to a “concept map” of the domain

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Traditional Course StructureCA 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

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Domain AnalysisEvidence 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

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Domain Map – The Big PictureEXPLAINANALYZESYNTHESIZEHypothesis GenerationHypothesis TestingGoal (What do you want to know?)Process (How to determine what you have)Functional MotifsStructural MotifsAssembly MotifsTOOLBOXRepresentational SystemsQuantification Systems

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ComparisonDomain as practiced Scientific literature spread equally between these three subdomains Domain as taught Textbooks and standards found only in Toolbox and Analyze subdomain

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Full domain map

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Big ConceptsStructure Relation to properties Functional group Emergent properties (bonding pattern  molecular interactions - 3 d structure) Transformation Physical transformations and chemical reactions Energy and motion Heat Molecular motion Built with styrofoam balls, magnets, and then put on a vibrating table Water, gold and plastic

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Mixed Reception

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Last Updated: 8th March 2018

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