Teaching of Analytical chemistry - ACS Publications

The Problem in Perspective. HP here are three different conno- tations I wish to attach to the word “perspective” in reviewing the problem of teac...
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SPECIAL REPORT A symposium

of papers presented at the 160th National ACS Meeting, Chicago, Illinois, September,

1970

H. A. LAITINEN Department of Chemistry, University of Illinois, Urbana, II!. 6 1 8 0 1

ANALYTICAL

Teaching of Chemistry

The Problem in Perspective THERE ARE THREE different connotations I wish to attach to the word "perspective" in reviewing the problem of teaching of analytical chemistry. The first connotation is that of the time scale. Each of us tends to measure trends in terms of his personal time scale usually back to "when I was a lad." This brings me to the early 1930's when I was an undergraduate and the late 1930's when I was a graduate student. At that time it can be fairly stated that there were perhaps a dozen schools in the United States that could be regarded as centers of graduate study in analytical chemistry. Typically in each school there was a single dominant professor and perhaps one or two others active in research in this field. In contrast, Dr. Stuart P. Cram presented a survey at the last Pittsburgh Conference on Analytical Chemistry and Applied Spectroscopy, which was later published in "Research and Development." In this survey it was found that 137 of the 176

Ph.D.-granting chemistry departments offer the Ph.D. in analytical chemistry. Of the remaining 39, some are trying to recruit staff members in this specialty while others are consciously avoiding this field. Prom such statistics one may infer that the long-term trend has clearly been for the growth of analytical chemistry both on an absolute and on a relative basis as a graduate specialty. Unfortunately, this tells only part of the story. During the rapid expansion of undergraduate schools in the 1950's and 60's, the supply of new Ph.D.'s in analytical chemistry was inadequate to meet the demand. The result was that analytical courses were often assigned to instructors with inadequate backgrounds in this field, with a consequent tendency to shortchange the analytical offerings, especially at the advanced level. This is not to say that the offerings deteriorated on an absolute basis, but that they did not keep up with the rapid developments in the science. Many students enter-

ing graduate work have had, and still have, an inadequate understanding about the field of analytical chemistry. Thus the shortage of graduate students and of new Ph.D.'s was perpetuated. During the past 10 or 15 years there has been a mixed trend regarding analytical chemistry as a graduate discipline. Some schools have deemphasized analytical chemistry while others have greatly strengthened their analytical programs in recent years. Why is this? The deemphasis, where it has occurred, has been coupled with an increase of emphasis Of theory at the expense of experiment, and with an "exclusion of definition" of analytical chemistry as a research discipline. That which is fundamental can be reclassified, and that which is methods-oriented can be dismissed as inappropriate for academic research. Here is a danger. If we classify analytical chemistry as an applied field, and if we recognize a Ph.D. as a research degree, then we run the risk of being classified out of departments that want

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only "pure," not applied research. My point is that analytical chemistry is indeed an applied science, but it is not only an applied science. It is also a basic science. Here is also a point for industry to consider. A Ph.D.-level scientist is trained for research—he is not just a more highly skilled operator. An analytical organization should have, in addition to a service philosophy, a research philosophy, that first of all encourages keeping abreast of research findings in the literature, and secondly, encourages investigation and publication of improved methodology. To reduce it to its simplest terms, the group should be problem-oriented and not sampleoriented. Samples should originate from problems, not the other way around. Turning now to undergraduate curricula, I wish to discuss these more fully in another context but at the moment let us summarize the most important changes that have occurred during the past several decades, as they affect analytical chemistry. Qualitative analysis has been greatly decmphasized, first by shifting it into the general chemistry laboratory and second, by greatly decreasing its content. Classical quantitative analysis has been decreased in emphasis, especially with regard to gravimetric procedures and multiple-component analysis. Third, a large number of courses in practical analysis—i.e., steel analysis, rock analysis, water analysis, and gas analysis—that were common early in the 20th century have been dropped. In place of these offerings, courses have emerged in instrumental analysis, sometimes subdivided by area such as speotrochemical, electrochemical, and separations techniques. Quantitative analysis courses have undergone marked revision toward a more fundamental approach in lectures, toward modernization of techniques, toward using more instrumentation, and toward changes in the nature of the samples. Some of these developments are to be discussed in detail in today's symposium. The point I wish to make at this time is that contrary to some statements expressed by our nonanalytical colleagues, analytical offerings have in fact under38 A

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gone deep-seated changes over the years, changes at least as deepseated as those in any other branch of chemistry. Turning now to the second perspective, that of distance, it may be of interest to compare American teaching methods with those in Europe. Prior to World War I, Germany was dominant in chemistry, not only in Europe, but throughout the world. The German chemistry curriculum, which served as a pattern for many other countries, placed the various branches of chemistry essentially in the order of their historical development. Analytical chemistry, both qualitative and quantitative, was strongly tied to inorganic chemistry. Organic chemistry stressed synthesis, with elementary microanalysis as a necessary confirmation of composition. Physical chemistry was a later arrival on the scene, and correspondingly it came late in the curriculum. The strength of the classic German system was in its thoroughness and in its uniformly high standards from one institution to another. As far as analytical chemistry is concerned, its weakness was that, coming early in the curriculum, it did not benefit from a fundamental physical-chemical approach, nor was it concerned with organic or biochemical materials. To this day a weakness in the German system is in its inflexibility. Individual schools arc not free to experiment with changes in courses and curricula as in America. As a result the undergraduate curriculum has lagged more and more behind research practice. Instrumental methods were to some extent incorporated into inorganic, organic, and physical chemistry but separate courses in instrumental analysis did not evolve as in the U.S.A. Even today, analytical chemistry is seldom recognized in German universities as a discipline in its own right. Professorships, when they exist, are usually tied to chairs of inorganic chemistry. Partially compensating for the lack of analytical courses per se is a greater stress in physical chemistry lectures and laboratory on topics that would be classified as analytical chemistry in the U.S.A.

ANALYTICAL CHEMISTRY, VOL. 42, NO. 14, DECEMBER 1970

Ironically, the most progressive countries today as far as analytical teaching is concerned, are the ones who were least tied by tradition to the classic curricula and who were more flexible toward change. Wherever professors with a modern outlook chanced to be in a situation that permitted change, courses were developed somewhat along the lines familiar in American institutions. Outstanding, if isolated, examples could be cited in France, Spain, Italy, Holland, Czechoslovakia, and the Scandanavian countries. Last year, in visiting several Yugoslavian universities, I noticed some significant developments in curriculum departures from the classic tradition. Not all the developments I shall Cite occurred in any one school but each reflected individual efforts of staff members. First, rather than giving tip on qualitative analysis, there were improvements using spot tests, catalytic reactions, paper chromatography, flame spectra, and the like. Second, physical chemistry laboratory courses were introducing analytical-type experiments. Third, modernized, although noninstrumental, experiments were being introduced into classical quantitative analysis courses. These included ion exchange, complexometric titrations, and nonaqueous titrations. Fourth, some research instruments were being shared with laboratory courses. In looking at analytical chemistry throughout Europe, one is forced to the conclusion that wrhile certain courses and certain individual professors are outstandingly good, the general level is distinctly below the present standards in the U.S.A. There is one particular respect in which European teaching has lagged significantly behind American and that is in instrumentation. Advanced instruments of course are common in research laboratories, but little systematic use is made of them in course work. I t is not just a matter of economics, as some would maintain, but to a large extent it is a matter of attitude. If instruments are considered as fixed pieces of equipment for making measurements rather than as devices to be made, altered, and experimented upon, then of course

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there is an enormous inertia against using valuable instruments for teaching. In recent years in a relatively few European schools, courses have been introduced in chemical instrumentation as distinguished from instrumental analysis. Further development in this direction is strongly needed if modern analytical chemistry is to take its rightful place in European chemical curricula. The third type of perspective is concerned with the relationship of analytical chemistry to chemistry as a whole and to other branches of science. It stands to reason that as the total body of knowledge increases, adjustments must be made in courses and curricula. These adjustments naturally take on the direction of more emphasis on broad principles than on specific facts, and a modernization of laboratory teaching to correspond with changes in the outside world. Especially during the past decade, curricular innovations have stressed departure from the traditional boundary lines within chemistry. General chemistry has been detached from inorganic chemistry and infused with ideas and material from organic chemistry, biochemistry, and physical chemistry. Quantitative experiments have been introduced into the laboratory, although not so much in the form of analytical procedures as experiments designed to illus-? trate chemical principles and to teach quantitative technique. Advanced courses have been designed to blend the laboratory experience of the students from the various types of chemistry and to bring it more nearly into line with the actual work of practicing chemists. Herbert Hoover, in his presidential campaign in 1928, described prohibition as "a great social and economic experiment, noble in motive." Similarly these curricular experiments are noble in motive but, alas, often as unworkable in practice as prohibition was in its day. The new curriculum purports to draw upon improvements in high school courses, to avoid duplication by minimizing descriptive detail, to stress basic principles instead of isolated facts, and to introduce the beginning students to 40 A

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the methods of modern chemistry with materials of significance to excite their interest. Unfortunately, our high school courses are uneven in quality. The very courses that are supposed to supply the descriptive detail are often themselves so devoted to studies of abstractions and generalizations that students never get exposed to many bread and butter details of chemical behavior. A student can hardly be expected to become excited over the nuances of trends in chemical structures or energetics without a substantive background of experience in chemical behavior. Similiarly in our haste to put the most sophisticated instrumentation into the hands of the students at the earliest possible time, we have tended to ignore the little details of quantitative technique without which the most sophisticated measurements are meaningless. It is not that the traditional boundary lines are inviolate, on the contrary there is real merit in considering laboratory practice in chemistry from a unified, generalized viewpoint. It is just that we should not attempt to generate an instant sophistication either in the theoretical or the practical aspects of chemistry. It appears to me that there is now starting a period of réévaluation of curricula, and that there is real hope for achieving balance both in theory and experiment between tradition and innovation. Furthermore, I believe that analytical chemists should play a leading role in curricular reform for they have the background and interest in laboratory instruction to a degree possessed by no other type of chemist and after all, chemistry is a .laboratory-oriented discipline. On the other hand, it is not only futile but unbalanced, to demand that analytical instruction retain all of its old virtues in modern curricula. For example, time spent in calibration of weights and glassware or in performing multicomponent gravimetric analyses can surely be spent to better advantage using present day experimental methodology. I t seems to me that analytical chemists have tended to two extremes—on the one hand, being ex-

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ceptionally slow to give up traditional approaches to teaching laboratory skills, and at the same time introducing an increasing variety and complexity of advanced instrumental measurements. In this latter regard wo have far outpaced our colleagues in other branches of chemistry but in the former, we have tended to lag. Just as the theoretical approach of the physical chemist has pervaded all branches of chemistry so has the instrumental approach pervaded all branches of experimental science. Analytical chemists sense a loss of identity when organic chemists adopt gas chromatographs (even though they still call them vpe's) and infrared instruments into their everyday work and into elementary courses. Biochemists have been much more oriented in recent years toward instrumental measurements and automated laboratory techniques. Inorganic chemistry, like organic chemistry, has been revolutionized both with regard to theory and experiment. Curiously enough, the physical chemists, with whom we have a great deal in common, have often been the least progressive in modernizing laboratory instruction. This, I believe, is caused by the pervasion of all other branches of chemistry by the concepts of physical chemistry with the result that the physical chemists themselves have moved away from the laboratory and toward theory. It appears to me that the best hope for a sound "interdisciplinary" course in chemistry is for the full participation of analytical chemists in the teaching as well as the formulation of such courses. The objective of interweaving organic, inorganic, and even biochemical experiments with modern analytical techniques and making them relate more closely to the actual experience of chemists are, of course, meritorious. The dangers are a lack of sufficient emphasis on accuracy and technique and also a tendency to omit certain topics altogether because they do not fit the organic or biochemist's concepts of how the chemist works. Likewise, there is often too little time for topics such as the theory of methods, sources of errors, and sampling.

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In considering analytical chemistry in universities, we should not forget the significant number of people, some trained as analytical chemists and some not, who are doing analytical work in departments other than chemistry departments. This is not all service work either as witnessed by the number of research papers originating outside of chemistry departments. During the next decade we can anticipate a significant growth in some areas—for example, clinical chemistry and environmental science— with a large analytical component. The question is whether these will be allowed to develop without the influence of chemistry departments. This is largely up to these departments to decide, and the decision will affect their strength and influence in the years ahead. If chemists decide that only "pure" chemistry has a home in chemistry departments, then a larger fraction of the chemists on university campuses will reside in other departments. Today there is a distinct trend in this direction. Chemists, in general, and analytical chemists, in particular, should take active part in planning and operating these new chemistry-oriented enterprises, which will give valuable research support to chemistry. Today we are to hear of several examples of innovations in course structure and content. It is encouraging to note that these new approaches are being developed by analytical chemists on their own initiative. Courses in analytical chemistry just as in other branches of chemistry should take into consideration the needs of nonspecialists in the early courses and of specialists in the advanced courses. They should devote themselves to fundamental principles, and also they should relate to real experience in many foreseeable developments in science. Analytical chemistry will continue to be a vital component in many existing branches of basic and applied science. With such a broad basis and with the increasing emphasis on relevance of science and technology to the problems of society, we may confidently predict a resurgence of analytical chemistry in the years to come.

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Circle No. 34 or Readers' Service Card A N A L Y T I C A L CHEMISTRY, VOL. 4 2 , NO. 14, DECEMBER 1 9 7 0

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