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Developing and Using Conceptual Computer Animations for Chemistry Instruction
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K. A. Burke, Thomas J. Greenbowe, and Mark A. Windschitl Department of Curriculum & Instruction and Department of Chemistry, Iowa State University of Science and Technology, Ames, IA 50011
Students who can solve quantitative problems by the use of an algorithm are unsuccessful when answering a similar question posed at the particulate-nature-of-matter level or conceptual level (1, 2). The common errors and misconceptions exhibited by students when solving conceptual problems in kinetics (3), electrochemistry (4–6 ), equilibrium (7), and solution chemistry (8) have been reported. The abstract and dynamic nature of these topics makes them particularly difficult for students to comprehend. In response to the emphasis instructors currently place on the molecular representation of chemistry and on conceptual understanding, several chemistry textbooks (9–11) now include diagrams and illustrations focusing on the molecular view and provide endof-chapter problems involving the particulate nature of matter (PNM). However, dynamic chemistry processes such as gas phase equilibrium, collisions of molecules, and electrochemistry are visually represented in these textbooks by static diagrams. Only a handful of studies report instructional strategies, techniques, or uses of technology that might prove successful in the remediation of chemistry misconceptions (12– 14 ). Because students often have difficulty visualizing, understanding, and remembering how dynamic chemical processes occur, the use of computers to display dynamic motion offers a means to help students understand complex chemistry concepts (15–17). A computer animation is a series of visual images displayed in rapid succession on a computer screen, providing the illusion of motion. Instructional computer animations can be constructed so that dynamic visual images communicate abstract ideas, concepts, and processes to students. A conceptual computer animation should be designed to provide a visualization of one specific chemical process. The animation can be at the atomic or molecular level of representation, thereby helping students gain a better understanding of the concept at the PNM level (15, 18). Representing a chemistry event correctly is the first step toward successful problem solving, and representation is an important aspect of conceptual understanding (19, 20). Although commercial computer animations illustrating chemistry phenomena are available (21–24), most chemistry instructors find flaws in the images, animation sequence, and the chemistry content and prefer not to use them (25). The availability of low-cost, powerful microcomputers with multimedia capability, the decreased cost of professional animation software, and new, cost-effective multisync projectors have opened the door for faculty members to develop and use their own instructional computer animations (26 ) independent of textbook publishers. W An extended version of this article is available on JCE Online at http://jchemed.chem.wisc.edu/Journal/issues/1998/Dec/ abs1658.html.
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Developing Computer Animations Although it is possible for individual faculty members to develop computer animation sequences on their own, it is more efficient to have an animation design team work together to develop and produce the animations. The team should consist of the instructor, another chemist with expertise in the topic to be animated, a computer graphics illustrator, a computer animator, a computer programmer, and an instructional designer (27). Identifying a single concept or principle is the first step in the development of an animation (28). An analysis of mistakes made by students on quiz and exam problems and science education journal articles identifying chemistry misconceptions provide insights into student difficulties and are excellent sources of ideas for animation sequences. The next step is to construct a series of storyboards (28), or at least an outline of the major points, including rough diagrams. Each storyboard should contain as much detail and information as possible in order to convey exactly how the chemist wants the animation sequence to be portrayed. For example, the size, color, and shape of any atoms, molecules, surfaces, solutions, etc., should be specified. Animation sequences that play for 20–60 seconds seem to work best, so the sequence should be short and focused. Some characteristics of effective instructional animation sequences are: Short: 20–60 seconds per concept Accurate chemistry content Option for accompanying text or audio narration explanation Panel with pause, forward, reverse, and exit control buttons Nonlinear navigation Addresses a misconception reported in the literature Interactivity, decision making, and prediction incorporated for active learning Appropriate assessment and feedback Provides an opportunity to construct knowledge WWW and local file server compatible Cross-platform compatible Permission to use copyrighted material, or a release form on file Faculty-tested, student-tested, classroom-tested
Developing a Conceptual Computer Animation: The Standard Hydrogen Electrode Analysis of student responses to quiz and exam problems in a college general chemistry course revealed that many students had difficulty understanding the functions of and chemical processes occurring in an electrochemical cell involving a standard hydrogen electrode (SHE). A conceptual
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Information • Textbooks • Media • Resources
computer animation that portrayed the chemical processes occurring in the SHE at the molecular level was developed. Software programming can be done in an animation program such as MacroMedia Director (29). Director is a powerful and sophisticated object-oriented animation software program that promotes user interactivity and decision making. A scripting language in Director, called Lingo, allows animators to build interactions. Scripting is the writing of commands that allows users of the animation to interact with the presentation. Users can explore specific aspects of the SHE in more detail after viewing a molecular level representation of the dynamics of the Zn-SHE cell. Figure 1 shows three frames of a conceptual computer animation sequence. When the animation is played, the viewer sees a representation of several dynamic chemical and physical processes: ion migration in the salt bridge, oxidation at the zinc electrode, reduction at the standard hydrogen electrode, and electron movement in the wire. The user has the option of selecting a box around the zinc electrode, the salt-bridge, and the SHE. Using a mouse and clicking on the hot spot navigates to another animation representing an atom-level (PNM-level) view of that area. If the area around the SHE is selected, the animation sequence displays just the processes occurring at the SHE. The animation shows a representation of pairs of hydrogen ions (shortened form for hydronium ions) reduced to hydrogen molecules on the surface of platinum atoms. The hydrogen ions are smaller than the hydrogen atoms. The chemical equation for this process is displayed at appropriate times in the animation sequence to remind the viewer of the specific chemical reaction being animated. This SHE conceptual computer animation is currently available on the World Wide Web at http://www.public.iastate.edu/~iachemed/FIPSE/ homepage.html and will be available for at least one year from the publication date of this article. Once this animation sequence was produced, reviewed by an electrochemist, and pilot tested with students, it was easy to develop a companion copper-SHE electrochemical cell animation. Using Conceptual Computer Animations When conceptual computer animations are used in conjunction with chemistry lecture demonstrations, students are better able to make connections among the microscopic, macroscopic, and symbolic levels of representation (30). For
example, using electrochemical cells animations (31) along with lecture demonstrations of the Zn-Cu, Zn-SHE, and SHE-Cu electrochemical cells (32) enhances student performance on both quantitative and conceptual electrochemical problems (16, 17). Computer animations designed to be used as part of an instructional presentation in the classroom work best when instructors do their own live narration. Either text narration or voice narration enhances the animation and provides students a simultaneous presentation of visual and verbal information (33, 34 ). This practice is consistent with the contiguity principle (35, 36 ) and the dual coding hypothesis (37 ). If animations are incorporated as part of a lecture presentation, then the animations should be available for students to view after class, perhaps in a computer lab or on the World Wide Web. The animation can be modified for student use by adding text or voice narration, using software such as SoundEdit 16 (38) or RealAudio (39). The text or narration should be kept to a minimum, assisting the viewer in understanding the main point of the animation, rather than distracting the viewer (40, 41). Using cooperative learning or a conceptual change approach to teaching along with animations can increase students’ understanding of chemistry (17, 42). Hardware and Software Recommendations Microcomputers with a fast processor (>240 MHz), a minimum of 32 MB of RAM, a minimum of 2 MB of VRAM, a large internal hard disk drive (>600 MB), Ethernet network access, and expansion slots for multimedia enhancement tools are preferred for developing high-quality computer animations. Pentium PCs or PowerMacs are preferable. It is desirable to have an external drive, such as a 230-MB magneto-optical drive or a 100-MB Zip drive, for backing up files. Once an animation has been developed, cross-platform conversion (e.g., from Mac to PC) should be done. The animation should be played on several different types of computers, powerbooks, etc., to check for compatibility with various screen sizes and for accuracy of the color palettes. Macromedia, Inc., offers a several high-quality, integrated, cost-efficient animation development tools. Freehand (43) is a professional-quality computer drawing program used to create excellent two-dimensional and acceptable pseudo-threedimensional images (shaded to appear three-dimensional). Extreme 3D (44), Ray Dream Designer (45), and Specular
Figures 1. Three frames of a conceptual computer animation sequence.
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Infini-D (46 ) are software applications used for creating highquality three-dimensional objects and virtual reality threedimensional scenes. Photoshop (47 ) is the software of choice to “clean up”, enhance, modify, or combine digital images. Images created using Freehand and Extreme 3D are easily imported into Director. Director animations can be created on either Macintosh or Windows-based computers. By including a hot spot on the screen, users can use a mouse to click on it to execute an associated script or command. Including interactivity allows users to control and interact with the animation program, rather than merely watching it. Simple scripting allows users to answer questions and receive feedback. Users can also pause the animation, repeat it, and advance it forward or backward one frame at a time. Nonlinear navigation to another part of the animation or another instructional program can easily be programmed. Technology innovations have dramatically influenced how chemistry instructors can present information to students. Animations created with Director are able to be viewed on the WWW by using Shockwave (48) technology and a Web browser such as Netscape (49). When placed on the WWW, Shockwave files are transported across the Internet, then decompressed and played back on the user’s computer by a Shockwave plug-in. One of the strengths of Shockwave is that students can play the animations on PCs running Windows or on Power Macs. For classroom presentations, there are many portable “one gun” multisync projectors that provide excellent images in terms of color and sharpness, excellent light projection levels, and excellent transitions for viewing computer animations. The new multisync projectors are lighter, more stable, and easier to focus than their predecessors. Copyright Issues Chemistry instructors who develop software must be aware of the U.S. Copyright Act, especially Section 106 (P.L. 94-553), the audiovisual copyright law pertaining to computer software programs, visual images, sound, and copyright owner (for digital access see http://www.law.cornell.edu:80/usc/17/). Abrams has a good review and layperson’s interpretation of the copyright and fair use law pertaining to multimedia (50). To incorporate someone else’s color digital images, photographs, diagrams, graphs, illustrations, movies, music, etc., it is necessary to obtain permission from the copyright holder. It is best to create in-house images, diagrams, graphs, illustrations, and sounds for incorporation into instructional software programs, even for “local, on-campus” use only. Summary Multimedia technology has advanced rapidly within the past two years. In particular, it is now possible to distribute multimedia presentations via the World Wide Web. Faculty members should work with a design team who have knowledge or expertise in instructional design, computer animation, and graphic and sound production. Developers of computer animations must be aware of copyright issues concerning the use of images, graphs, illustrations, or sounds. The use of computer animations along with demonstrations presents all three level of representation: microscopic, macroscopic, and symbolic. When instructors take the time to emphasize the PNM and conceptual issues through the use of computer 1660
animations, students’ understanding and performance on conceptual exam questions increases. Using computer animations does take some additional time. Instructors should decide whether it is more important to “cover” or “uncover” material, and whether to adhere to a “less is more” chemistry curriculum (51). Literature Cited 1. Gabel, D. L.; Samuel, K. V.; Hunn, D. J. J. Chem. Educ. 1987, 64, 695–697. 2. Nurrenbern, S. C.; Pickering, M. J. Chem. Educ. 1987, 64, 508– 510. 3. Lynch, M. D.; Greenbowe, T. J. Computer-Based Instruction That Stresses Student Misconceptions in Chemical Kinetics; presented at the 210th National Meeting of the American Chemical Society, Chicago, August 23, 1995. 4. Allsop. R. T.; George, N. H. Educ. Chem. 1982, 19, 57–59 5. Garnett, P. J.; Treagust, D. F. J. Res. Sci. Tech. 1992, 29, 1079– 1099. 6. Ogude, A. N.; Bradley, J. D. J. Chem. Educ. 1994, 71, 29–34. 7. Bergquist, W.; Heikkinen, H. J. Chem. Educ. 1990, 67, 1000– 1002. 8. Smith, K. J.; Metz, P. A. J. Chem. Educ. 1996, 73, 233–235. 9. Olmsted, J.; Williams, G. M. Chemistry: The Molecular Science; Mosby: St. Louis, MO, 1994. 10. McMurry, J.; Fay, R. C. Chemistry; Prentice Hall: Upper Saddle River, NJ, 1995. 11. Silberberg, M. Chemistry: The Molecular Nature of Matter and Change; Mosby: St. Louis, MO, 1996. 12. Sanger, M. J. Identifying, Attributing, and Dispelling Student Misconceptions in Electrochemistry; Ph.D. dissertation, Iowa State University, 1996. 13. Lynch, M. D.; Greenbowe, T. J. A Computer Simulation of the Method of Initial Rates; presented at the 14th Biennial Conference on Chemical Education, Clemson, SC, August 7, 1996. 14. Lynch, M. D. The Effects of Cognitive Style, Method of Instruction, and Visual Ability on Learning Chemical Kinetics; Ph.D. dissertation, Iowa State University, 1997. 15. Williamson, V. M.; Abraham, M. R. J. Res. Sci. Teach. 1995, 32, 521–534. 16. Sanger, M. J.; Greenbowe, T. J. J. Chem. Educ. 1997, 74, 819– 823. 17. Sanger, M. J.; Greenbowe, T. J. J. Res. Sci. Teach. 1997, 34, 377– 398. 18. Noh, T.; Scharmann, L. C. J. Res. Sci. Teach. 1997, 34, 199–217. 19. Herron, J. D. The Chemistry Classroom: Formulas for Successful Teaching; American Chemical Society: Washington, DC, 1996. 20. Herron, J. D.; Greenbowe, T. J. J. Chem. Educ. 1986, 63, 528– 531. 21. Chemistry At Work: Image Database for Chemistry [a laser disc]; Videodiscovery, in cooperation with McGraw–Hill: New York, 1991. 22. Prentice-Hall Chemistry Laserdisc; Prentice-Hall: Englewood Cliffs, NJ, 1994. 23. Kotz, J. C.; Vining, W. J. Exploring Chemistry [a CD-ROM]; Saunders: Philadelphia, PA, 1995. 24. CHEMedia: Connections to Our Changing World [a set of four laserdiscs]; Prentice-Hall/Simon & Schuster Education Group: Upper Saddle River, NJ, 1996. 25. Greenbowe, T. J.; Burke. K. A. The IGCN-FIPSE Summer Workshops; Department of Chemistry, Iowa State University: Ames, 1996 (unpublished report submitted to the U.S. Department of Education). 26. Gelder, J. I.; Gettys, N. S.; Wheeler, J. A. Chemistry Animations [a CD-ROM]; Oklahoma State University: Stillwater, and Synapse: Lincoln, NE, 1994. 27. Overbaugh, R. C. J. Res. Comp. Educ. 1994, 27, 29–47. 28. Kemp, J. E.; Smellie, D. C. Planning, Producing and Using Instructional Technologies, 7th ed.; HarperCollins: New York, 1994.
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Information • Textbooks • Media • Resources 29. Director [computer program]; Macromedia: San Francisco, 1995. 30. Russell, J.; Kozma, R.; Jones, T., Wykoff, J.; Marx, N.; Davis, J. J. Chem. Educ. 1997, 73, 233–235. 31. Greenbowe, T. J. J. Chem. Educ. 1994, 71, 555–557. 32. Ward, C. R.; Greenbowe, T. J. J. Chem. Educ. 1987, 64, 1021– 1023. 33. Mayer, R. E.; Anderson, R. B. J. Ed. Psychol. 1991, 83, 484–490. 34. Mayer, R. E.; Anderson, R. B. J. Ed. Psychol. 1992, 84, 444–452. 35. Reiber, L. P. ETRD 1990, 38, 77–86. 36. Reiber, L. P. J. Ed. Psychol. 1990, 82, 135–140. 37. Paivio, A. Mental Representations: A Dual Coding Approach; Oxford University Press: New York, 1990. 38. SoundEdit 16 [computer program]; Macromedia: San Francisco, 1995. 39. RealAudio [computer program]; RealNetworks: Seattle, WA, 1997. 40. Mayer, R. E.; Bove, W.; Bryman, A.; Mars, R.; Tapangco, L. J. Ed. Psychol. 1996, 88, 64–73. 41. Reiber, L. P. Ed. Technol. Res. Design 1996, 44(1), 5–22.
42. Birk, J. Multimedia and Group Activities To Enhance Learning in General Chemistry; presented at the Symposium for the Recruitment and Retention of Chemistry Students at the 139th 2YC3 National Conference, San Antonio College, San Antonio, TX, November 16, 1996. 43. Freehand [computer program]; Macromedia: San Francisco, 1994. 44. Extreme 3D [computer program]; Macromedia: San Francisco, 1995. 45. RayDream Designer [computer program]; RayDream: Mountain View, CA, 1995. 46. Infini-D [computer program]; Specular: Amherst, MA, 1996. 47. Photoshop [computer program]; Adobe: Mountain View, CA, 1994. 48. Shockwave [computer program]; Macromedia: San Francisco, 1996. 49. Netscape [computer program]; Netscape Communication Corp: Mountainview, CA. 1996. 50. Abrams, A. H. Multimedia Magic; Allyn and Bacon: Boston, 1996. 51. Lloyd, B. W.; Spencer, J. N. J. Chem. Educ. 1994, 71, 181–183.
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