PACIFIC SOUTHWEST ASSOCIATION O F CHEMISTRY TEACHERS ANALYTICAL CHEMISTRY-HOW SHOULD BE TAUGHT1
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RAYMOND W. BREMNER Fresno State College, Fresno, California
ONMY officewall hangs a picture showing two men in knee britches. They are working with a telescope with a large wheel mounted on a table on which rests a prism. An explanation under the picture reads: "Joseph Fraunhofer 1787-1826, Inventor of the Spectroscope, Was the First to Measure and Designate the Dark Lines of the Solar Spectrum." 1800 is 150 years ago. Yet absorption spectra have reached analytical chemistry only within the past few years. Why was this principle not applied sooner? It would seem that either Fraunhofer and his followers did not know enough analytical chemistry or the analytical chemists did not know enough physics. This points to one thing that needs careful consideration: how much specialization is desirable in teachmg analytical chemistry? On the one hand, in large universities there is a strong tendency to specialize very highly in the graduate years. This is carried down to some extent into the undergraduate program. On the other hand, in the small college there is the opposite tendency. The professor has a larger variety of classes and usually less research time. Another factor to consider is the student. Chemistry (and chemical engineering) majors fall into groups, according to the fields for which they are preparing: (1) those preparing for research positions after four years of training, (2) those planning to teach chemistry and related subjects in secondary schools, and (3) those planning graduate work for an advanced degree. A chemistry major may desire at any time during his training to concentrate on analytical, inorganic, organic, physical, biochemistry, or some even more specialized field, and should be appropriately advised. Aside from chemistry majors, we have another group that requires analytical chemistry. It is made up of premedical, predental, prephamacy, laboratory technician, geology, engineering, biology, etc., students. Although this discussion will center upon training analytical chemists for industry, we must keep in mind training for other types of chemical work and determine how these fit into the over-all program of educ* tion. 'Presented in a panel discussion at the October 21, 1950, meeting of the Association.
An analytical chemist going into an industrial organization or research group should, I think (1) have suitable personality-be adaptable, agreeable, honest, enthusiastic, etc., (2) have ability to express himself clearly and concisely, both orally and in writing, (3) be well grounded in basic principles of chemistry and related fields, especially analytical chemistry, (4) be trained in manipulative skills, and (5) have the ability to do original thinking and to make sensible interpretations of data. These qualifications in the trainee would also he very desirable in applicants for other positions open to the graduate. For the prospective teacher additional training and practice in methods of presentation and dealing with younger people should be included. The analytical chemistry teacher can help obtain such people in several ways. One very effective way is by precept and example. Another is by support of and participation in a careful screening program for students entering college and choosing a major. For example the time worn "liquidation" method of failing 40 per cent of the students in each semester of freshman chemistry and 40 to 60 per cent in the first semester of sophomore chemistry is antiquated and unfair as a method for selecting desirable trainees. It also creates had public relations. Admission requirements, testing, advising, and guidance into appropriate fields are much more effective. Such a program is being developed a t Fresno State College. Of course, there will always be screening by achievement standards set in courses. I know of no better place to teach the virtues of honesty than in quantitative analysis. The nature of the subject leads to honest endeavor in practice and in theory. There is a tendency among chemistry majors to belittle such subjects as English and social sciences. Some of the questions on written chemistry examinations can be given in such a way that the student must begin with a capital letter and end with a period in giving a definition, describing a method, or explaining a theory. Mistakes in English should be marked. Such words as clearly, concisely, briefly, and fully should appear frequently in examination questions. There is
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JOURNAL OF CHEMICAL EDUCATION
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no more eloquent declaration of ignorance than the Sophomore Year inability of a college graduate to speak and write his ~h~~~~ md problems stressed. Procision is required in the native language well. Every chemistry major should laboratory. Normax glassware, class S weights (one ~ e per t student), and chainomatic balances with magnetic dampers are fully realize this as soon as possible. used. Burets, pipets, and ureights sre calibrated by major What subject matter should be included in students. chemistry? We should not lose sight of the traditional I,, Volumetric analysis and one or instruments, qualitative and quantitative, volumetric and gravi1, ~ ~ l and ~grllvimetric ~ ~ t ~and ione ~or tuTo metric chemistry. Volumetric and gravimetric analysis instruments for nonchemistry majors. 11. Gravimetric anslysis and anion and rarer element qudihelp many students, for the first time, really to undertative analysis (maora). stand what chemistry is all about. Some experience with ores, alloys, and substances difficult to In addition to these and a few other methods used in organic chemistry we now recognize the importance of dissolve is obtained, including some of the rarer elements. the following general procedures: Junior Year Spot testing Electroplating Refractometry Potentiometry Viscosimetry Microscopy and crystal structure Polarimetry Calorimet~y,nephrlometry, fluorescence, reflectance, and color (visual or pbotaeleotrio, using inirared, visible, and ultraviolet) Spectrophotometry (including emission, abso~ptian, fluorescence, and reflectance; in the ultraviolet, visihle, infrared, and microwave) Conduetomotry Interiacisl tension Polerography Gas analysis Ion exchange Radioactive tracer techniques Microanalysis X-ray diffraction Raman analysis Electron microscopy Mass spectrometry
I. Qualitative organic analysis, required for B.S., optional for A.A. degree. (Taught hy an organic chemistry professor.)
Senior Year 11. Instrumental analysis, required for B.S., optional for A.B. degroc. Prerequisites: two semesters quantitative, two semesters organio and physical chemistry (letter may he taken concurrently). I or 11. Analytical laboratory research project, honors course for the better students. (Written and oral reporbs required.)
Graduate Year 11. Advanced quenbitative analysis-theory, reading af the literature, reports, may include laboratory work. I or 11. Thesis in analytical ehemist~y;analytical laharatmy research project; seminar topics.
This program is adequate to supply the needs of each type of student. I t is broad enough to permit some specialization in analytical chemistry by students planning careers in industrial work or in teaching, especially at the junior-college level where analytical chemsubject. There are doubtless additional methods of analysis istry is a According to recent articles, students beginning being develoFed. Automatic recorders are cially available for several of the methods listed and graduate work at Purdue University3 and other uniautomatic process controls based upon them are in use versities are especially weak in inorganic chemistry. A frequently quoted comment by Dr. Reedy, I believe, in some of the chemical industries. several years ago, ,"hen I mentioned the lack of of the University of Illinois, is, "There is no better in place to teach inorganic chemistry than in qualitative training in the theory and use of these ~ ~ ~ , colloid yalysis." The inclusion of anions and rarer elements chemistly to D", M ~ Bstanford's chemist, his comment was, '
