Robert J. Angelici Iowa State University Ames, IA 50011
What is Happening in Our Inorganic Laboratory Courses?
During the past 30 years inorganic chemistry has become a major and very diverse area of chemistry, important not only in our classrooms but also in industrial and government lahoratories. The breadth of the subject has posed problems for faculty seeking t o provide a useful hackground for their students. T o give students a "real-life" experience with a variety of inorganic compounds and experimental techniques, inorganic laboratory courses have begun to take root at most colleees and universities in this countrv. In a n attemDt to examine the purpose and content of these courses, I made an informal survey of 160 American universities with PhD ~ r o grams listed k t b e ACS Graduate Directory and 78 collkges (defined as those without P M programs) listed in the booklet, "Research in Chemistry at Private Undergraduate Colleges" by the Council on Undergraduate Research, Brian Andreen, editor. Several questions-were asked of an inorganic faculty member at these schools: (11What are the educational guals of the course? (2) Is a lecture an integral part of the lab? (3) What kinds of students take the course? (4) Is a commercinl lab text used, or are locally-prepared materials used? ( 5 ) Is a graduate laboratory course offered? In addition, they were invited to eive as manv details ahout their courses as thev wished. ~&.ponses were received from 82 (51%)of the 16; universities and 25 (32%) of the 78 colleges. The responses were divided into those universities or colleges which offered (1) an inorganic laboratory course, (2) an integrated laboratory course which included inorganic experiments, or (3) no inorganic laboratory experience. The numbers of respondents in each of these groups are listed below: Have an inorganic laboratory course
Have an integrated course, includes
Universities Colleges 35( 43%) 12( 48%) 15( 18%) 6( 24%)
inorganic Have no inorganic laboratory experience
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Journal of Chemical Education
32( 39%) I ( 28%) 82(100%) 25(100%)
Approximately one-third of the schools had neither an inorganic nor an integrated course. Many cited a lack of faculty, lack of resources, a small number of "real" chemistry maiors. and already having too many required courses in the cu& ulum as reasons for not having an inorganic ruurse. Some indicated that their students could do undereraduate research on an inorganic project. One college required its majors to do 4 semesters of research. one semester with each of four ~- facultv members in the four aieas of chemistry. Although I bad not intended to survey integrated courses involving inorganic chemistry, a modest amount of information was received. Some faculty indicated that including inorganic in an integrated lab course was viewed much more favorably by their colleagues than introducing a separate inorganic lab course into the curriculum. The integrated courses, as defined by the respondents, appeared to range from interspersing experiments commonly taught in standard disciplinary lab courses to developing completely new experie
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Robert J. Angelici received his degrees from St. Olaf College (BA, 1959)and
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Northwestern Universitv (PbD. 1962). After one year of postdacioral research as a National Science Foundation Postdoctoral Fellow at the University of Munich, he joined the faculty at Iowa State Uni- a versity in 1963and is now Professor and Chairmanof Chemistry. He was an Alfred P. Sloan Fellow and has received the Chemistry Department's Wilkinson Teachine Award (1911) and the Outstandine-~eacherof the ~ e a r ~ ~~,~ w a(1978) r d ~,in the Sciences ~~. and ~. at Iowa Srntr University He IS nuthor i d n w~drly-usedlaburatory texr and has p~lrliihrdw r r 11.5artides describing his group's research in organometallic and bioinorganic chemistry.
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ments which really do integrate ideas and techniques from several disciplines. The largest number of institutions (7) integrated inorganic and organic synthesis. Three comhined inorganic and physical laboratories; four integrated inorganic, analvtical..and ohvsical: and four others described their entire program as inie&ated. Many of the labs included regular lectures to provide some chemical background as well as to discuss experimental techniques both in terms of specific experiments as well as for applications in other situations. In almost all of the integrated courses; locally prepared materials were used. often borrowing exoeriments from commercial lahoratorytextsand the ~o;rna?of Chemical Educotion. As indicated bv some of the respondents, the marnitude of the inorganic component in these courses depends importantly on the extent of inorganic facultv involvement in formulating and teaching the co&es. ~his~involvement, as well as t h i availability of resources and small class size, seems to be especially important in developing a high quality integrated lab course. The inorganic lahoratory courses a t the 47 colleges and universities that reported having them varied considerably. At essentially all institutions, it was a one- or two-credit required course (either specifically required or as a lahoratory credit reauirement) for chemistw maiors. A few students from other majors also took the couke. Enrollments varied from 3 to 40 students with 10-15 heing a fairly common number. Although some courses were taken by students in their senior year, most were taken by juniors. The number of scheduled class hours ranged from 3 to 8 hours per week. At some schools, work was allowed in the labs during the scheduled hours only, while at others students were allohed to work in pairs at dmost any time. Since it is not possible to provide equipment for all students simultaneously, several experiments were usually being performed at the same time. Sixty percent of 2 indicated that a lecture was those resoondine- to ouestion . part of t i e course. In almost all cases, the lecture was labrelated and covered safetv or svnthetic and s~ectroscooic techniques to be used in the exp&ments. At one university, each of the students was reauired to eive . a %-hour lecture on an experimental technique. The goals of these courses were normallv to teach advanced laborat& techniques not encountered by the student in other courses and to expose the student to some of the breadth of inorganic chemistry. A fairly common approach was to use experiments from Angelici,' often supplemented by the use of exoeriments from a varietv of other sources. Also m i t e common was the use of experiments from both Jolly2 and Angelici.' In addition, experiments were taken from Adams ,~ Syntheses, and and ray no^,^ Pass and S ~ t c l i f f eInorganic the Journal of Chemical Education. A substantial number of locally-developed experiments are in use in a large number of schools. Indeed, some lab courses consist entirely of such procedures. I would encourage instructors to publish these experiments in the Journal of Chemical Education, so that others might make use of them. Those which have already been published in this Journal are used widely in inorganic courses. Synthetic techniques which are frequently taught in these courses make use of the following equipment: tube furnace, electrolysis apparatus, inert atmosphere facilities such as Schlenk tubes, inert atmosphere hags or boxes and vacuum lines, and high pressure autoclave. Two schools even do a svnthesis of his(benzene)chromium derivatives usine a vaporized metal atom reactor. ~hotochemical1~-promoied syntheses are also included in a few courses. Purification of products is achieved frequently by chromatography (gas, liquid, or thin-laver), sublimation, or crystallization as in the reiolution of en&tiomers. Methods of product characterization commonly include UV-visible, IR, NMR ('H and sometimes 13C),ORD (and sometimes CD), and Mossbauer spectroscopy, as well as magnetic susceptibility, solution conductivity, and sometimes mass spectrometry and X-ray diffraction. Other experiments demonstrating inorganic
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techniques include kinetic studies of substitution reactions, the determination of eauilibrium constants for the binding of metal ions by various iigands, vapor pressure and molecul& weight measurements on a vacuum line, and elemental analyses of products. Although techniques and studies included in a given course vary greatly from one school to another depending upon the available resources, the course emphasis is commonly synthesis and characterization. Of t h e different types of compounds prepared in the courses, coordination compounds are the most popular; those involving the representative elements and organotransition metal der{vatives are not far behind. The paucity of bioinoreanic experiments sueeests that some new additions in this .... area would be welcomed. Also there are few experiments involvine the lanthanoids and actinoids. Except for tuhe furnace synth&es, solid state chemistry is not adeq"ately represented. The Solid State Suhdivision has recognized this problem and is collecting solid state exprimentswhich are-now in use. Anyone interesced in ohtainine a list or copies of individual experiments may write to DI.-E. ~ o s t i n e ;(Department of Chemistry, The University of Connecticut, Storm, C T 06268).5 In some inorganic courses, the student spends the last 2 or 3 weeks developing a mini-research project, which is frequently an extension of one of the experiments. This research experience becomes a much more important component in courses in a few colleges and universities. In some cases, the student is toldto synthesize and chqacterize a specific compound. I t is then up to the student to search the literature for the best method of preparation and methods of characterization. One college &;ids structured experiments entirely by requiring its students to carry through two half-semester research projects. The latter type of course is rare, and most inorganic faculty have opted for a course which offers students a choice.of - - exneriments for which chemicals and facilities are readily at hand. A strong research orientation is more feasible when enrollments are small. Student reports on their experiments were sometimes as modest as a record of the experimental procedure and conclusions in their notebook. In other cases, a more formal report including an introduction and experimental, results, discussion, and conclusion sections. A few required reports written in the style of a paper in Inorganic Chemistry. At one university, students gave oral reports on their procedures and results. Some university respondents indicated that lahoratory courses were not appropriate a t the graduate level. At many others, graduate students were encouraged to take the u i dergraduate course, or a slightly modified version for graduate students, if they had not had a previous inorganic lab experience. Some stressed the value of having graduate students serve as teaching assistants in the undergraduate course. The results of this brief survey indicate that inorganic laboratorv courses are in a continuine oeriod of evolution. and all stagesof this evolution are repr&nted in schools across the countrv. In the past 30vears. . .these courses have undereone major c&ges in cdntent and acceptance in the undergradmte chemistry curriculum. In many schools, they are regarded as an integral, and dynamic, part of the curriculum. I am hopeful that thev will not only continue to grow and provide a new vitality tb chemistry programs but a& spread to those colleges and universities where they have yet t o gain a foothold. 1 Angelici, R. J., "Synthesis and Technique in Inorganic Chemistry," 2nd Ed., W. B. Ssunders, Co., 1977. 2 Jolly, W. L., "The Synthesis and Characterization of Inorganic Compounds," Prentiee-Hall, Inc., Englewood Cliffs,N.J., 1970. 3 Adams, D. M., and Raynor, J. B., "Advanced Practical Inorganic Chemistry," Wiley &Sons,Ltd., London, 1965. "ass, G., and Sutcliffe, H., "Practical Inorganic Chemistry," 2nd Ed., Chapman and Hall, Ltd., London, 1974. 5 See also proceedings of the State-of-the-ArtSympmium on Solid State Chemistry published in this J o u r d (57, (1980j1and available as an offprint from Journal Offprints, 238 Kent Road, Springfield, PA 19064. Volume 57, Number 11, November 1980 1 767
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