Producing Computer-Literate Chemists Ian C. Bowater, Ian G. MeWilliam, and Margaret G. Wong Swinburne University of Technology John Street Hawthorn. Victoria 3122, Australia
I n recognition of the increasing dependence of society on com~uters.we have recentlv restructured our chemistrv and biochemistry undergraduate streams to ensure that we produce computer-literate chemistry graduates. The major change was the inclusion of compulsory subjects called Computers i n Chemistry i n the final four academic semesters. We decided t h a t t h e major t h r u s t of these subjects should he the use of the computer as a tool to do chemistry more productively. Hence we have concentrated on the chemical use of commercial software packages rather than extending the computer science topics beyond the compulsow BASIC ~ r o a a m m i n adone in semester 1. w e also decized t h a t m o s t of t h e hardware aspects should be studied in the instrumental science subiects in semesters 3 and 4 rather than in the Computers inVchemistry subjects. Because these subjects are not done by the biochemistry stream, we included topics on communications and data acauisition in the Computers i n Chemistry subject in semester 7 (semesters 5 and-6 are spent working in industry).
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Structure, Management, and Assessment of Computers in Chemistry Subjects Each week students attend a 1-h lecture followed by a 2-h session i n a computer laboratory. For each year a detailed workbook of several hundred pages i s used for both the lectures and the set exercises to be done during the laboratory session. The lecture i s normally used to set the context for each laboratory class. This may include a description of the operation of a new software package, a lecture on a traditional chemistry topic (e.g., kinetics), or a n ex~lanationof a data-handling ~rocedure. +he computer laboratory coLt'ains twenty 486 IBM compatible computers connected to a sewer. Students can book similar computers in other rooms on the campus to complete the exercises and work on assignments. Many students have access to computers a t home although compatibilitv problems sometimes arise esoeciallv with 360K disk driveiand printers. One demonstrator can supervise up to 25 students in a room rontamng 20 romputirs if the iktructions in the set exercises arc clwr, detaled, and carefully debugged. Although it is desirable to have only one student per computer, two students can work together effectively when they have comparable ability and both contribute to the task. However, when students work in pairs the noise level is greater, and they are more inclined to socialize. ARer noticing that some students were keen to finish the exercises as quickly as possible, we inserted calculations, questions, and graphs (drawn to scale) in the exercises to force a deeper level of understanding. These were particularly important for mathematical or conceptually difficult topics. i n 1990 and 1991 we allowed some of the students to do the exercises a t home. However, in 1991 a substantial proportion of these students did not do sufficient work i n semester 4 and failed, so in 1992 we made performance in class count 20% towards the final mark. Any student who has done the work before class is judged by their answers to the calculations and questions in the workbook. Most of the subjects are assessed by a combination of performance in class, individual assignments, and an open-book exam. The assignments are designed to allow students to use
a soi7svai-e package creatively to process chemical information. When possible the completion time for an assignment is in the first half of the semester to reduce the workload on the students a t the end of the semester. In the exam, students use their workbook to answer the exam questions. This encourages students to treat the calculations, questions, and graphs in the workbook seriously. Course Content for Semester 3 The topics covered are 1. Personal computer hardware, software, and computer codes 2. DOS commands and DOS Shell for disk, subdirectory, and file operations 3. Spreadsheetsusing Latus 1-2-3(I) and AS-EASY-AS( 2 ) 4. Graphics using spreadsheets 5. Word processing using PC-Write (3) 6. Impart of ASCII files into spreadsheets and export of worksheets ta a word processor 7. Molecular modelling using Desk Top Molecular Modeller (4) 8. Simulation of chromatographic resolution and reaction
kinetics using spreadsheets We devote two weeks to the first two topics. We teach the syntax of DOS commands because it reinforces the basic concepts of disk drives, subdirectories and files and because some students only have an older version of DOS a t home. We then devote five weeks to topics 3 to 6. Along with many others (5-7)we have found that spreadsheets are ideal for repetitive and "what if' calculations and for the graphical presentation of information (8).
Spreadsheet Exercises. The exercises include the creation of spreadsheets that .combine marks from three tests where each test can be marked out of a different number and given a different relative weighting compare how a principal of $1,000 would accumulate for ten years at three different interest rates calculate a line of best fit All three exercises reinforce the copying of formulas and "what i F calculations. In the latter two exercises the information is displayed graphically. In the graphics exercises, students also learn how to plot curves and vertical lines. The first assienment has been desiened to use the skills developed so far. Each student is req&ed to use a spreadsheet to import unprocessed chemical data, process it, display i t in aagraph, i n d finally export i t to aword proc&sor where i t i s incorporated into a well-presented report. The exercises in the three weeks devoted to molecular modelling include displaying molecules in different ways, for example, plane projection and bond projection comparing the optimized structure with the crystal structure (before and after optimization) discussing the energy terms before and after optimization of the structures
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The second assignment uses molecular modelling to revise and enhance understanding of the geometry of organic compounds. Each student is given the structure of a different molecule, which must be built, optimized, and comp a r e d w i t h t h e s t r u c t u r e i n t h e Cambridge crystallographic data base (9). In the last two weeks, spreadsheets are used to calculate and display a chromatogram containing two peaks for given values af the parameters t M ,n,k', and u (10)
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the concentrations of reactants, products, and intermediates versus time in reversible and consecutive first-order reactions far given values of rate constants
buffer capacity. Finally alpha plots are used to study how t h e relative concentration of each chemical species of H3P04and EDTA changes as the pH changes.
Calculations and graphs are used to maximize the learnine concevts, for example, resolution of the -of auantitative . peaks and half-time of the reaction.
Measurement a n d Statistics Exercises I n the measurement and statistics exercises spreadsheets are used to
Course Content for Semester 4 The topics covered are 1. Spreadsheet macros (3 weeks)
2. Acid-base calculations and graphs using the Acid-Base Package (11)(3 weeks) 3. Measurement and statistics (6weeks) Use of Macros Many students get frustrated writing spreadsheet macros because this task reauirrti attention to all the details. the keys to manually exeSo we start gently by cute a eiven kevstroke macro. After loading the macro and notinguthe named ranges, the macro i s run i n single-step mode. Then the students enter given modifications to the macro and run i t again. After mastering the basics of writing and debugging keystroke macros a
