Observations on an Individualized Approach to Teaching Analytical Instrumentation The use of real samples, special group projects, and open-ended individualized research experiments in teaching analytical chemistry have been described in this J~urnal.'.~Over the last two years we have altered our junior-senior level course in analytical instrumentation making extensive use of real samples and individualized analytical projects. While there are several similarities hetween our approach and those cited, we report here several observations and variations which have not been described. We hope instructors considering such an approach will find these additional observations helpful. While we continue to use several conventional experiments to review selected instrumental techniques (uv-vis spectrophotometry, gas chromatography, AA and flame photometry, potentiometry, palarography, and caulometry, plus a basic review in electronics), these are completed during the first 7 of 30 three-hour laboratories, after which each student completes a minimum of six individualized analytical projects using real samples. The present two page List of 82 analyses, given to the students at the beginning of the semester, is divided into four categories: (1) major or minor inorganic constituents, e.g., lead in paint, (2) trace inorganic constituents, e.g., fluoride in water, (3) major or minor organic constituents, e.g., fatty acids in soap, (4) trace organic constituents, e.g., riboflavin in vitamin pills. Working individualy, students select analyses and decide on an analytical method after researching the literature and consulting with the instructor. The instructor and TA's make sure individual students are aware of available instrumentation appropriate for their projects and provide assistance in approaching a given instrument or instrumental technique. Students assume responsibility for the footwork necessary to locate and arrange for chemicals and equipment (through our chemical stores) and in many eases the sample itself. We have heen pleasantly surprised with the ability of students to cope with these sometimes tedious preparatory steps and believe this type of prelab preparation is more realistic and, in view of the extensive contact with the literature and the techniques required in taking representative samples, providing pedagogical advantages over conventional laboratory experiments. During the second half of the semester, each student gives two informal 20-30 min presentations describing two analyses to the class during the biweekly lab-lecture meetinp. The general format is to describe the nature of the sample, available methods of analysis, the method chosen, and the experimental results. Since accuracy of results can not alwavs he established. students draw com~arisonsto e r ~ e c t e dvalues eiven in the literature or on commercial labels and comment on the raperrmental p r e r w m and his her confidence in the results. The other students are encouraged to ask questions durrng and after the presentatmn. Thr use of real samples definitely generates interest among the students and the d ~ s r u s s r ~ ninvariably s provide an excellent learning environment for huth th? audents and instructor. The i n s t ~ c t 0 1 scan not and need not he aware of all the analytical methods for the listed projects. Our key to successful implementation of such projects has been to communicate to the student the nature of the sample and the analytical goal of the chosen analysis. This accomplishes the very important step in any analysis of beginning with a mecise statement of the problem. Armed with this information, students have little difficulty finding methods for analysis in the literature. The approach has significant merits difficult to observe in the more conventional approaches, those being the skills and confidence developed by the students far analytical pmblem-solving without fear of initial ignorance and imnroved abilitv to use the literature eonstructivelv. We believe students " eain an imnroved understandine of real analyt~callaburatmv operations and problem^, a- a result uf t h ~ sexperience. A copy of the analyses and information on student repunrng sndevnluetrm pmredures~~,availsble "pun request.
' Huonu. J. A.. and Fashing. -1. I., J. CHEM. KI)UC., 50.61: Wehry, E. 1. .. J CHEM. EDCC., I7.Hl3 119701.
University of Nebraska Lincoln, 68508
(1973).
James D. Cam Virgil K. Olsen R. Ken Force Neil D. Danielson
Volume 52, Number 2. February 1975
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