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Figure 10. Two second display of noisy FID. The program will be provided at no charge to anyone sending a dlsk and prepaid mailer, otherwise the cost is $5.00. Checks should he made oavablc to the Vireinia Tech Chemistry Department and s i n i t o H. M. Hell, chemistry 1)euartment. Vireinia l'ech. Hlackshure. VA 24061. Unless an'alternate con%guration'is specifiei,' the program provided will require VGA graphics and a n 8087 math coprocessor. Versions that will run on CGA and EGA, with or without the 8087, can be supplied upon request. A text file that contains a tutorial session with 20 suggested exercises will also be provided.
Raw Data to Finished Report: Microcomputer Assisted Estel D. sprague3 University of Cincinnati Cincinnati. OH 45221-0172
The integration of microcomputer use into our undergraduate program has received increasing emphasis in recent years. The focus of that emphasis is a junior-year course, the theme of which is accurately reflected in the title given above. Microcomputing applications in the first two years of our program have consisted of the use of drilland-practice software and computerized pre-lab quizzes for freshmen. Although plans for more extensive applications at this level are now being formulated, especially for the laboratow profram, truly substantial use of microcomputers presentiy begins in the first quarter of the junior vear in the course to be described here. Phvsical-Analvtical Measurements. This is a 3-credit, reqGred course, designed to prepare our students for other courses to follow. Its principal goal is to train our chemistry majors to view and make use of microcomputers just as professional chemists do: as ordinary, everyday tools, to be employed routinely, rather than just in special situations. Course Content Course content can be divided into four areas.. uursued more or less simultaneously as the quarter progresses: general mechanics of computer use, data and uncertainty
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3~resentedat tne 1991 Comp~tersIn Cnem ca Ed~caton Workmop. Case Western Reserve U n versry, Cleve ana, OH. 'Since the methods and procedures being taught, rather than specific software packages, are the principal concern in this course, the students are permitted to use any high-qualitysoftware which may be available to them. The maioritv use the student edition of Lotus 1-2-3 and Wordperfect,although several other packages are also used.
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Figure 12. Transformed spectrum after phasing and expanding. analysis, spreadsheet operations, and report writing. Materials used include the error analvsis text bv Tavlor (12). spreadsheet and word-processing~so~ware~ an: nonlin: ear, least-squares software (13). Some instruction in the routine mechanics of microcomputer use remains necessary, since a preliminary survey each year continues to reveal a significant fraction of our students with minimal prior experience. A little time is spent describing the internal workings of microcomputers and, especially, the care and use of floppy disks. Although students are increasingly likely to have access to computers at home or a t part-time workulaces. manv still carrv out much of their work in a departmental computer lad. Thus. some instruction is necessarv concernine the lavout and i s e of the computers, laser priiters, and other dehces in this facility. Touics in the analvsis of data and their associated uncer~~~~~tainiies are organized aroudd the book by Taylor. We cover much of this text by means of lectures, problem sets, and reading assignments, going substantially beyond the text in the area of model-fitting calculations. In particular, we discuss and make use of model evaluation methods described earlier in this Journal (13).Required, in general, are nonlinear, least-squares calculations, where emphasis is placed on the often misunderstood fact that it is nonlinearity in the adjustable parameters, ruther than in the experimental variables. to which reference is made. Thc simplification in error analysis resulting from the use of such methods is also pointed out as an added benefit. Spreadsheet procedures are covered in detail in lecture, illustrated by means of a portable computer and liquid crystal overhead display panel (as are all specific computer manipulations). Over a period of several weeks many of the typical business-oriented exercises found in the manuals accompanying such software, extended with appmpriate chemistry examples, are assigned as homework. The students are required to become reasonably proficient in using essentially all of the capabilities of the spreadsheet software except for macros, which we have not found time or need to include formally. Since regression analysis is carried out easily in most spreadsheet software packages,
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Volume 70 Number 12 December 1993
997
it is also discussed. with e m ~ h a s ion s recomizine the verv various cases, such as the analysis of results in a flash pholimited set of conditions under which its use is st&isticalIi tolysis kinetics experiment and in a stopped-flow kinetics meanineful. The discussion and exercises are desimed to experiment, among others. reinforcc two particular views of spreadsheet software: as In addition, many of our undergraduates carry out reclectronic notebook and as " s u ~ e rcalculator. " The students search projects with individual faculty members. The data soon recognize it to be a high?; convenient tool for staring, manipulation and report-writing skills gained in this retrieving, manipulating, and preparing graphs from, course prove highly beneficial to them and to their advitheir experimental data. One particularly common and imsors in this setting. portant kind of graph is stressed, that in which experimenConclusion tal points are plotted, along with a best-fit, or a theoretically calculated, smooth curve.. The course described above leads to a genuine integrahe issue of improving the report-writing skills of our tion of microcomputing into the curriculum at the junior undergraduates IS seriously addressed. Our efforts include and senior level for our undergraduate majors. Motivation several sienificant features. all of which aid in the Drocess. is high throughout the course, and it is especially helpful First, thestudents are required to use ~ o r d - ~ r & e s s i n ~ that new data analvsis and error analvsis Droblems or oresoftware for all of their writing, making editing a much cedures are accompanied by new tools to use in their trkatless painful task for them. This necessitates that they ment. The use of microcom~utersbv the students in subseachieve a certain level of ~roficiencvin the use of the softquent chemistry courses, undergraduate research projects, ware, and this is accomplkhed in a k a n n e r similar to that and studies outside chemistry, has become truly routine, for the soreadsheet software, including lectures and homejust as it is for practicing chemists, thus fulfilling the priwork assignments. Second, we adopt; well-defined, caremary goal of the course. fully explained report format, that in the physical chemisLiterature Cited try laboratory manual by Shoemaker, et al. (14), one of the 1. Bent, H. A. Chsmieni Dmonstratiom, A Hondbmk for Tpoehers of chemutry: texts used i n a later laboratory course. Particular Shahhashid, 6. Z.,Ed: U n i ~ r s i t yof Wisonsin: M a d i m , 1983: Val. 2, pp i i i emphasisis placed on learning to organize a report propm iii. . .... erly, separating results from discussion, experimental 2. Atkinson, K E. An Infmduction toNumrimi Anoly~k,2nd ed.; W~ley:New York, 1989; pp 341356. methods from results, etc. Third, a type of peer review is 3. Atkinson, K E. An Inlmduetlon to Numrkul Analysis, 2nd ed.; TKlley: New York, employed, in which students exchange first draRs of re1989; pp 4 2 W 8 . 4. Melka, R F:Olsen, Gan:Beavers,Lindsai;Draeger, J.A. J. Cham Edur 19% 69. ports with each other for evaluation, write up their criti596598. cisms, and then revise their own reports. Both the final 5. Gray, P ; %on, S. K Chemiml Oseiliatiom and Imtobilitrrs: Nan-linear Chemical Kimfics; Clarendon: Oxford, 1990, pp 371386. drafts and the critiques of classmates' reports are counted Jordan, P. C. CharnkdKimtie and 7kmport;Plenum: New York, 1979; p 214. 6. in arriving a t grades for each student. Although report 7. A1bedy.R.A. Physimi Chemist?, 7thed.; John Wlley andSona: NewYmk, 1937; pp writing is likely to long remain an area difficult and someC ---l i ? -A Q 8. Ryan.D. L M&m OmphkCornm~nk1rti1r1r:Re~etiti-H~U,E~g1~w0d CWW~,NNN what tedious to teach, and one in which much further imJemey, 1966 provement can be made, the methods employed here have 9. Diehl. S.; Apiki, S.Eyfe IJanusly1989). 162-174. 10. Blunt, J. W. J. Cham. Edue IssS,GO, 97-98. had some success, as evidenced by performance both in 11. Estler, Ron C. J Cham. Educ 1991,68,A220-A222. this class and in various subsequent courses requiring 12. Taylor, J. R A n hmduellon to ErmrAnoiysk;University Science Books: Mill Valwritten reports. ley, CA, 1982. 13. Sprague. E. D.:Larrsbee, C. E., Jr J C k m . Educ Is& 65, 238-242. 14. Shoemaker, D. P: Garland, C.W ; Nibler, J. W . ExpPdmnla in Physiml Ckmistq, Sample Experiments 5th ed.;McCraw-HiU: New York, 1989; pp 1%26. Riehsrdson,T H. J Cham. E due. 1891,68, 310311. 15. To reinforce and interconnect all of the material pre16. M3ler.B. J Cham.Educ. 1989.66.267-270. sented, the students begin with their own raw data and progress to a f ~ s h e dreport for two simple experiments, making use of microcomputers a t all appropriate stages Answer to Puzzle on page 963 along the way. In one experiment the pressure-volume behavior of air is experimentally measured by each student, Original Chemical Word Letter followed by a determination of whether Boyle's Law is adWord Removed equate to describe the observed behavior. This experiment provides a n excellent vehicle for demonstrating a variety GELD GEL D of methods for arriving at a statistically meaningful answer to the question. MEAT MET A The second experiment has sometimes been involved NICE ICE N with distributions of masses of a large number of pennies, WATER WAITER I similar to that described by Richardson (15).This experiGENE GENRE R ment requires the use of many of the database features of POLAR POPLAR P the spreadsheet software, as well as the application of imTRAP TRP A portant statistical tests. On other occasions a buoyancy exISLE periment, similar to part of one described by Miller (161, ILE S has been employed. We have not yet included an experiLITER LITER T ment explicitly concerned with computerized data collecPHE E pH tion per se, but our students are exposed to this aspect of BLUFFER BUFFER L computer use in several experiments in later lab courses. "
Subsequent Computer Use The skills acquired here are applied throughout the remainder of the students' program. This specifically includes both the routine use of spreadsheet software for data analysis and the writing of lab reports in the format just learned. It also extends ta the use of the nonlinear, least-squares program and model evaluation procedures in
998
Journal of Chemical Education
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