I provocative - ACS Publications

to he disenchanted with what they see in the world. It just might he ... So we now have merged .... have to know whether conjugated double bonds are l...
0 downloads 0 Views 5MB Size
I provocative Two ~ u ~ ~ o r t Views ive

Where the Action Is

...

A

popular cry today is for relevance. Most of these cries seem to come from youth who seem to he disenchanted with what they see in the world. It just might he that their plea is valid. However, myopia may he the problem rather than the world's irrelevmce. I'd like to bring into focus a part of the big picture of chemistry, analytical chemistry, which I feel has real relevance. For another very real reason, the relevance of analytical chemistry needs emphasizing. The sources of chemists are the colleges and universities. At one time chemistry was rather centralized. As it grew, it divided into the proclaimed disciplines called analytical, physical, inorganic, organic, biochemistry, etc. Expenence has led scientists to realize that such defined categories are artificial and too confining. So we now have merged disciplines such as physical organic, analytical biochemistry, etc. But, the academic departments of chemistry appear to he responding to this melding of disciplines in an uncomfortable way for us. There's a trend toward absorbing analytical chemistry into any or all other phases of chemistry. Analytical chemistry does belong everywhere functionally; what chemist can draw any conclusion from his laboratory work without analyses? However, that breed of chemist who does analyze things needs to he considered as a more distinctive hreed than can he possible when academically he's totally integrated into other fields of chemistry. What i s Analytical Chemistry?

Superficially, there are two broad phases of analytical chemistry; the determination of (1) what is (in) it, and (2) how much. Immersed in these is the need for an analytical chemist to he concerned with how to best answer these questions. He's responsible for critically evaluating current techniques and deciding whether to use them as they stand, to improve them, or to develop new ones. One trait of an analytical chemist is an immense amount of pride in his profession, hut he's not a slave to it. I n his search for techniques to answer the basic questions posed above, he's willing to pick up a research technique being used by other kinds of chemists and apply it to analyt,ical problems. Some analytical chemists are embarrassed when they realize that many of t,he analytical tools they use so effectively and so routinely didn't originate in analytical laboratories. But he takes pride in his role in elevating the technique to prom(Continued on p. 59, col. 1) 58

/

Journal of Chemical Education

Like Cleopalra's Beauty

...

In most universities, the chemistry curriculum is under active review, especially as a result of the Westheimer iteport,l and its outgrowth-the Hammond-Gray2 curriculum. Analytical chemistry and its traditional place in the chemistry curriculum have been heavily and persistently attacked by chemists in universities. Differences in the role and status of analytical chemistry in the chemistry curriculum stem from the definition of analytical chemistry. Analytical chemistry, like Cleopatra's beauty, is of infinite variety -hence numerous definitions have been proposed in the literature. However, most of these definitions present only certain aspects of analytical chemistry and are therefore unnecessarily restrictive. To me, the most appropriate definition is that analytical chemistry is the science concerned with the characterization of chemical systems, theoretical and experimental study of systems of actual or potential analytical significance, interpretation of the existing methods of analysis, and development of new methods of analysis. If this is too comprehensive a definition to identify analytical chemistry, it must be remembered that the nature of modern analytical chemistry makes it too pervasive to be contained within narrow confines. The above definition is admittedly cumbrous, and also suffers from lack of precisely demarcated areas of chemistry to be called analytical chemistry. However, such lack of precision in areas is inherent in the nature of modern analytical chemistry. Before I suggest some possible ways of improving the role of analytical chemistry, I should like to survey courses in analytical chemistry in the revised curricula in universities. Although the pattern varies among universities, certain general trends have appeared which are common to the revised curricula. First, there has been a very sharp increase of emphasis in the freshman chemistry courses on structural chemistry, chemical dynamics aud equilibrium, and chemical bonding. Secondly, there has been increasing pressure within chemistry departments to remove the classical course in quantitative analysis as a separate entity from the sophomore year and integrate it into the freshman chemPresent,ed as an invited position paper a t the Seminar on the Teaching of Ardytieal Chemist,ry, organized by the Analytical Chemistry Division of the Chemical Institute of Canada, hIontreal, May, 1969. ' Chem. Eng. News,43, 72 (1965). ' Chem. Eng. News, 44,4R (1966).

(Continued o n p. 59, col. 8)

inence and improving it in scope or reliability. The analytical chemist still has these challenging responsibilities to determine the best, old or new, ways to answer the "what" and "how much" questions. The "what" covers a pretty broad waterfront. Known or suspected components are certainly obvious. But, to be alert for suspected components requires understanding the chemistry involved in generating the sample and the chemical effects of the history of the sample. I n analyzing a partially hydrogenated ethylenic hydrocarbon, you naturally expect to find saturated and unsaturated species. But if you're analyzing for unsaturation by most halogenation schemes, you have to know whether conjugated double bonds are likely to form since they don't completely halogenate. Phthalate ester plasticizers seem to pop up in an ever increasing number of organic preparations. Knowing the chemistry of the sample should indicate whether such esters are possible components. Iinowing the history of the sample should disclose whether the sample or solvents used in its preparation ever came in contact with plastic lab ware. The "what" also covers the unexpected or "surprise" components. Herein lie some real challenges. The ~hthalateesters mentioned above might fall in this category, especially if the history lesson was incomplete or ignored. An effective analytical chemist is alert to observe and to recall unusual behavior of samples which shows up during his analysis. The "how much" also covers a broad spectrum of quantities from "pure" materials to parts per billion contaminants. Not all ppb level components are contaminants but may be functional necessities of the sample. Transistors wouldn't function if they were "pure;" they're intentionally "doped" with very small amounts of other elements in order to make them work. Some contaminants are tolerable, others are intolerable. A silicate glue that contains even a per cent or so of metals will still stick labels to a box. Furthermore, the glue maker doesn't have to worry much about what kind or how much of these metals is present. However, the transistor manufacturer is very concerned with both what kind and how much because he knows such contaminants seriously affect the performance of his product. There's another anglc of the "how much" question which moves from science into business. In commerce, prices of most products are based on some quality or composition criteria which assumes the ability to analyze the product and thus agree upon a price. Let's take an example. The United States imports over three billion pounds of green coffee a year. Green coffee contains about 8-12y0 water so the US. 'Limports" about 300 million pounds of water a year. At 40b/lb. for green coffee, this water costs $120 million. The price is adjusted, of course, depending, among other factors, on the water content. The analysis for this water has a standard deviation of about 0.2%. With 98%' confidence that the analysis reflects the true moisture level, this analytical "wobble" amounts to about $14.4 million a year. No wonder part of an analytical chemist's concern and responsibility lies in improving his methods. Such

istry laboratory. Thirdly, there has been an increased emphasis on chemical instrumentation and the physical chemistry principles which serve as the basis for instrumental analysis. Eventually, analytical chemistry will be emphasized primarily in only two required courses in the undergraduate curriculum: a freshman or sophomore course on quantitative chemistry and chemical principles, and a junior or senior course on chemical instrumentation and instrumental analysis. Some pertinent facts which should be considered are as follows . 1) As underlined by the Westheimer Report and the Hammond-Gray curriculum, the traditional organization of chemistry into analytical, inorganic, organic, and physical chemistry is no longer appropri&te,and in fact, is considered to present a barrier which limits one's perspective of the full role of chemistry. 2) As a result of (I), the undergraduate curriculum for the analytical chemist is the same as for the chemist in general and consists of courses which stress core concepts rather than factual knowledge. 3) Since the undergraduate curriculum is built around the core concepts, specialization in various areas of chemistry such as analytical chemistry can be done only a t the graduate level through advanced courses in specialized areas. 4) The PhD in chemistry who has been broadly educated in the fundamentals in all branches of chemistry is more suitable for creative research in analytical chemistry than the narrowly-trained PhD in analytical chemistry. There is an only too obvious inverse correlation between narrow specialization and lack of original ideas. 5-, ) The ~-~ financial constraint of a limited budget requires that the limited funds available are used to teach courses which give the best possible education in chemistry. Laboratory courses (including quantitative analysis) are given with inexpensive apparatus, with concentration on those techniques which are conceptually rich and are widely used also in other branches of chemistry. Thus, non-technological universities have neither the time (curricular restraint) nor the money (financial constraint) to teach professional courses in analytical chemistry. Such professional courses, although highly desirable, require teachers of analytical chemistry who are specialists (and therefore in great demand in industry) and sophisticated instruments which are very expknsive. 6) As Dr. W. D. Cooke3 of Cornell University said elsewhere, the fact that industry and government would have more analytical chemists makes no impact on universities-most university faculty members care little about the needs of industry and government. 7) I n revising the curriculum (as in most other academic matters), it is the larger and more prestigious universities that set the trend-other universities follow suit. If they do not, they lose high-quality graduate students, thereby starting the chain reaction-loss of top-notch faculty members, and loss of five-figure research grants which give financial support to research students-the vicious circle is now complete.

(Continued on p. 60, col. 1 )

(Continued on p. 60, col. 2)

-

Volume 47, Number I , b n u n r y 1970

/

59

improvements can very direct,ly mean dollars more wisely spent. Air, water, or land pollution is certainly a popular and relevant concern today. We often hear about the engineering effort at overcoming these problems, and the biologists come in for their sharc of publicity as they proclaim the effects of pollution. But, somebody has to tell the engineers what pollutants they have to control and how successful their control efforts are. Somebody has to tell the biologists the identities of the materials which are causing the effects they're publishing. That somebody is most likely an analytical chemist. I say most likely because he isn't always. Because of an acute shortage of this breed of chemist, other scientists must fill in for them. Thus, it's rather apparent that this relevant, current world concern requires both analytical chemistry and analytical chemists. It's not an exaggeration that the realm of analytical chemistry matches the realm of science. The organic chemist may use infrared spectroscopy to establish the identity or purity of his preparations. Viscositytemperature relationships are established by analytical measurement to help the polymer chemist; the physiological chemist's steroid profile was probably derived from gas chromatographic analysis. The biochemist may direct his future research efforts based on amino acid analyses provided by ion exchange separations and spectrophotometric quantitation. All of these scientists anchor their co~~clusions and determine their next experimental ventures as a result of analytical measurements. Academicians need to realize the breadth of study necessary to become an effective analytical chemist. The most serious problem they must meet is the trend toward reducing the number of formal courses being required. One or two semester courses in fundamental physical, organic, inorganic, and biochemistry are the meat and pot,atoes for the student in analytical chemistry because they allow him to better understand what his peers are doing in their fields. No analytical chemist can be all things to all men and experts in certain areas will evolve. A great asset to an analytical chemist is a willingness to learn new things; what he hears he has to place in perspective and fit the pieces together. He must have an open mind, a willingness to question prior conclusions in the light of new information. An analytical chemist is basically nosey for he's always trying to add to his mental "data bank." Much depends on the validity of his major product, a number, so he tends to be a skeptic and an unrelenting pessimist. He realizes any answer (number) he gives has some, error in it. How large and how important this error is is of real concern. He resists releasing premature analytical data because he knows that few tables of data or product specifications have any room for qualifications attached to an analysis report. To the neverending consternation of the sample owner, he presses pretty hard to find the analytical approach. It's establishing the history of the sample, it's looking for possible interferences in the analytical methods he has in mind, and

8) Today's high school graduates have been taught mathematics (including calculus) and the natural sciences on a much higher level than were their predecessors. Thus, it is now not only possible but is also necessary to stimulate and maintain their interest and to concentrate much more on advanced fundamentals of chemistry, mathematics, and physics than had been possible previously in the undergraduat,e education. Also, to avoid repetition of the Grade 13 chemistry laboratory, freshman chemistry has been revamped incorporating quantitative analysis which was traditionally given as a separate course in the second year. 9) As a result of their preparation to a higher level than before and their early exposure to abstract theories, the present-day students find theoretical work more exciting and challenging than laboratory experimentation. Quantitative analysis requires good manipulation and correct t e c h n i q u e ~ h o t , play h vital roles but are hardly exciting by themselves; when combined with highly routine procedures, they are a deadening experience. 10) Modern chemistry is dominated by abstract thoughts, and even in an experimental science like chemistry the emphasis is on more theoretical treatment and less experimental work. 11) Most academic chemists view quantitative analysis not as an area concerned with currently unsolved problems hut as an exercise in unexciting disciplinary technique. They think that the arguments in favor of its retention as a separate entity are like the arguments heard in the past that Latin and Greek should be required courses for the BA degree, because the disciplines were "good for t,he student." 12) Since courses cannot grow without limit, incorporation of new material always demands elimination of some subjects that have been traditionally considered indispensable to sound chemical education. I n the ever-growing competition for room in the chemistry curriculum, only those courses will survive and flourish which present new and exciting materials, which do not run up the student against dead ends of empiricism and frustrite him. 13) Finally, the quality of instruction in analytical chemistrv must be examined. Since t,he student willnow get his first exposure to analytical chemistry in freshman chemistry, the manner of present,ation and the quality of instruction given in the freshman year (as well as other levels) will decide the image of analytical chemistry among future chemists. It is therefore imperative that a true pict,ure of analytical chemistry as i t is actually practiced today is presented to him. Such a freshman course should expose the student to the spirit and practice of quantitative chemistry, and also provide some of the excitement that is found near the research frontiers of analytical chemistry. Now I shall deal with what should be and can be done within the limitations set forth earlier in this paper. 1) It is necessary for the teachers of analytical chemistry to become more concerned with and involved in the teaching of freshman chemistry. The initiation to analytical chemistry occurs here. 2) Analytical chemistry should be taught as it is practiced today, i.e., modern analytical chemistry with

(Continued on p. 01, col. 1 )

(Continued on p. 61, col. 2)

What is an Analytical Chemisl?

60 / journal of Chemical Education

~

it's the learning process of the analytical chemist. His reason for grilling a sample owner is to assure providing the best analysis possible or necessary. He has no business applying a method that costs $500 to run in order to answer a 10b question. At the opposite end of the egotist scale mentioned above is a trait which takes great courage and hard work to develop. That is simply to admit that he's not all knowing. He has to learn to admit he lacks sufficient expertise in an unfamiliar field or problem. Then, he he can either listen, read, and learn, or bow out. If the latter seems right, he must unselfishly suggest other analytical chemists or other laboratories where a better, more prompt answer can be found. But, he has to know these alternatives and this brings us back to the breadth of knowledge he must possess. One last characteristic, perhaps skill is a better word, that an analytical chemist must develop and employ is salesmanship. His analyses can often be at odds with other data, past experience, or preconceived conclusions. But if he's done his homework, his answer deserves all the salesmanship he can muster to logically and technically support his findings. As a salesman, the analytical chemist must know his wares, his methods, as well as his clients, and prepare himself accordingly. The Chemistry Needs of an Analytical Chemist

One last element of the relevance of analytical chemistry is an evolutionary one. I n more and more industrial settings, those who require analyses are more and more engineers and less and less chemists. Curricular pressures are squeezing chemistry courses out of nearly all engineering curricula. As a result, the analytical laboratory and its personnel are fast becoming the sole repository for chemical knowledge. Analytical chemists are thus increasingly involved in explaining chemical transformations taking place in given reactions. These mainly regard side reactions, since the intended reaction is usually pretty well understood by the engineer. The "what went wrong" question is often answered by recognizing a logical side reaction. At the same t.ime, the chemical knowledge that the analytical chemist has is an increasingly important asset, both to himself and his employer. A side benefit is that he gets involved in technical discussions with the engineers. He's in..+,he middle . -- . ...- . ...- ....nf . . t,hines: - ~ - ~-he's ---~-in ~ the , know. I admit there's a somewhat prejudiced opinion which threads tlLrough what's been said, At the same time, -T t,hink ........ t,herels ......- snhst,antiable evidence that analvtical rhemistrv is where the act,ion is. As lone: as anyone . ~ - ~ needs to'inow what is (in) it or how much& how-best analytical chemistry and the analytical to find ,.hemist will be the focal point of these questions and the source of the answers. How much more relevant can you get? ~

~

~

H. Whitney Wharton The Procter & Gamble Company Winton Hill Technical Center Cincinnati, Ohio 45224

stress on instrumental methods and separation techniques. 3) All courses in analytical chemistry should he taught rigorously as a science based on sound principles and not as techniques based on empiricism. The theoretical and experimental treatment should not only emphasize their importance to analytical chemistry but also to other branches of chemistry. Viability of courses in analytical chemistry would depend not on the analysis being a service to all branches of chemistry but on the contribution of the analytical topics taught in these courses to other courses in chemistry. 4) From the information received from some of the universities where quantitative chemistry has been integrated into the freshman chemistry laboratory, it appears that the experiment of teaching quantitative chemistry in the freshman year has not been a success and should be abandoned. 5 ) I n the first three years of the undergraduate curriculum (the Pass BSc program), there should be only two courses in which analytical chemistry is taught: a course in quantitative chemistry should he taught in the sophomore year; and a course in chemical instrumentation and instumental analysis, which should be taught in the junior year after the students have been exposed to courses in physical chemistry, organic chemistry, and inorganic chemistry. 6) Specialized courses in analytical chemistry should be taught as graduate courses. A more general course, e.g., electronic spectroscopy,electroanalytical chemistry, etc., can be taught also in the fourth year (the Honors BSc year). Advanced courses should be given by experts on those subjects. 7) Establish the need for the universities to be equipped to give also postgraduate professional courses in analytical chemistry leading to MSc degree in analytical chemistry, as are given by many universities in England-the most notable heing The Imperial College of Science and Technology of University of London. 8) Establish the need for the creation of new technological universities (as exist in the U.K. and Europe) or the upgrading of the existing institutes of technology. These bodies should be given the responsibility of teaching postgraduate professional courses in analytical chemistry leading to postgraduate degrees and diplomas in analytical chemistry denoting various levels of professional competence. 9) Since the present universities can only educate chemists in the fundamentals of theoretical and experimental chemistry and cannot give them professional training, industry (and other employers) must give then further on-the-job training. Most of t,he recrimination will end if the above responsibility in the training of analytical chemists is recognized and honored by both

Parties. Chuni 1. Chakrabarti Carleton University Ottawa 1, Ontario, Canada

Volume 47, Number 7, January 1970

/

61