Forget quant for freshmen - Journal of Chemical Education (ACS

The author argues that students should be given a full exposure of two or three semesters to the attractive, the unexpected, the predictable the entic...
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Forget Quant for Freshmen

It does not take any great measure of perceptive insight to realize that the teaching of chemistry, particularly with potential chemists in mind, is in dire straits. I t is obvious that without a good supply of students majqring in chemistry, the introductory courses will be reduced to a mere service function for students in other disciplines, and the upper division courses will be diminished to a near zero enrollment, especially in medium-sized and small inst,itutions. The trend in this direct,ion is fright,fullyimmediate. I n the first place, the general population of this country is so illiterate in science that it has never been assimilated into our intellectual culture. Until recently the average citizen has been neutral toward a subject which has appeared mysterious and complex to him. But now, faced with greater consciousness of such problems as nuclear, biological, and chemical warfare, pollution, and general destruction of the ecology, more and more people have become alienated against all science, even though they might admit they still do not understand it. Sharing this view is a large segment of the high school and college young people. Chemistry is taking the brunt of this movement, because specific chemicals (DDT, mercury compounds) and specific chemical companies are in the forefront of a very hostile public opinion. Furthermore, the job outlook for chemists and chemical engineers is dim and growing dimmer (1). When we reflect on the traditionally large defection of chemistry majors to other fields after a semester or two of introductory courses, the additional prominence of these new social, political, and economic forces indicates the easily predictable outcome of a drastic dimunition in the number of students choosing a career in chemistry. It behooves teachers of chemistry a t every level to do all in their power to conserve the interest and motivation of students who, in spite of the above mentioned pressures, have declared themselves fledgling members of the chemistry profession. The revolution undergone by the first-year course has been virtually unchallenged until quite recently. Less than three years ago, W. T. Lippincott (93) cautiously editorialized that the subject matter of modern courses just might be a little too much for the maturity of the present day student. Since then a few counterrevolutionists have attacked the alleged superiority of high school preparation and the choice of physical chemical topics and level of sophistication of freshman texts (5). The language of the dissidents has become more strident. Lippmann and Yager (4) describe some introductory texts as "appallingly bad." Conrad Ronneberg (5) describes the situation as one of "utter chaos." Although I am in general agreement with these critics, my remarks will not be concerned with their objections, but rather with one aspect of the 108

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Journal of Chemicul Education

content of the introductory college course which apparently most writers of laboratory manuals have accepted as desirable and necessary. I am referring to the increased emphasis on quantitative procedures. It is generally recognized goal of any science to strive toward a maximum degree of quantification. This characteristic of scientific activity is so pervasive that there has arisen a pecking order among scientists, which consists in looking down one's intellectual nose at sciences which are less subject to mathematical expression than one's own. Thus to physical scientists the biological sciences are obviously inferior; and to physical and biological scientists the social sciences are beneath comment on this score. This same attitude prevails within a given science, where more of an aura of excellence is attributed to any given portion of it the more quantitative it is. This viewpoint is probably quite harmless in itself, but when used as a rationale for pedagogical decisions it may well be disastrous. One striking and successful consequence of this philosophy in the freshman course has been the increase of quantitative procedures and the near banishment of qualitative analysis. I am not trying to "save" the latter, but I do object most strenuously to the use of magical words to bolster arguments for curricular changes. Those who advocate the full use of quantitative procedures in every possible introductory chemistry experiment will offer merely one word as the basis of their position. I n the answer to your, "Why," they will say, "It's quantitative." Of course, they may spend ten to thirty minutes (depending on how unprogressive you are) explaining the full import of the word, but it all ends up with the dogmatic and categorical statement that if it is quantitative it is better for the student. The implication is that the noblest aim of chemistry is quantification, and the future chemist better get with it as a freshman. It is my contention that the shift toward quantitative methods in the beginning course constitutes an educational mistake, and is a contributing factor to the decreasing numbers of chemistry majors. I n every type of human activity designed for pleasure or profit there are the dull moments. Although they cannot be eliminated, their impact frequently can be mitigated by making them occur a t a manageable time. For the chemistry student these dull moments are those which must be devoted to elementary quantitative analysis. As observed by C. L. Chakrabarti (6), this field "requires good manipulation and correct techniques-both play vital roles but are hardly exciting by themselves; when combined with highly routine procedures, they are a deadening experience." Replication is obtained only by meticulous attention to all the procedural details. It requires time and discipline to

obtain data of quantitative significance. The data must then be reduced by computation. Certainly there can be no dispute that such activities are among the least glamorous in the study of chemistry. Yet the science of chemistry would be incomplete without them. The future chemist must acquire a knowledge of quantitative work; but, the timing of his exposure to it is subject to discussion. I claim that to present this type of material in the freshman course is a fallacious conclusion derived from the widely held view of the snperiority of the quantitative. The drop-out rate of chemistry majors after one or two semesters of general chemistry is notorious. We teachers responsible for this course are not doing a good enough job of salesmanship. But insofar as we let quantitative procedures usurp a large portion of laboratory time we are committing pedagogical suicide. I t is simple psychology to present the carrot before the stick. I n chemistry the carrot consists in satisfying the scientific curiosity of the student, not only with the solid intellectual fare of concepts and theories, but also with a presentation of the romance, excitement, glamour, and relevance of chemistry as it continues its development. The teacher of first-year chemistry has a wide-open field, for the course is "general," and he can pick almost any topic he wants, and when he does so, it should be with the purpose of arousing and furthering the enthusiasm and commitment of his future professional colleagues. The same thing holds for the elementary organic course. The stick in the chemistry curriculum is the training given in quant,itative analysis. My plea is that the student should be given a full exposure of two or three semesters to the attractive, the unexpected, the unpredictable, the enticing parts of the chemical enterprise. Only then will we teachers have a rationale for asking the embryo chemist to take the dull moments in &ride. So my point here is that the time for teaching quantitative analysis is after the freshman year. It is not my purpose to give a broad and definitive discussion of this question, but I would like to present a few miscellaneous remarks. In the first place, although chemists like to describe their subject as a quantitative science, a little reflection will reveal that there are vast segments of it in which problems must be solved by analogy, elimination of qualitative alternatives, trial and error, intuition and guess-work, and luck. Placing a large number of quantitative experiments in the freshman year would simply give a false impression of the work of the average chemist. Then there is the assumption of the superiority of high school graduates over former generations. Even if we grant the truth of this statement, there can be no question that in spite of the "new science" and the "new math," freshman chemistry students who are forced to do yurlntirotiw rypc crpcriments hare a big pmblrm wirh the cnlculxtions. Even rct1cl1r1.swho irtsisr on t h k t\me of laboratory exercise admit this, yet they keep arguing " A

for more and more, while their students get frustrated with the intricacies of arithmetic, algebra, and logarithms, causing many of them to opt out even before the pleasant and rewarding vistas of chemistry are opened to them. Furthermore, from the freshman pedagogical point of view, an answer good to 0.1% is not superior to an answer of 1%,provided that the student can either see what the sources of error are, or that they are pointed out to him. But it does by no means follow that the beginner should be stuck with all the rigid procedures needed to achieve a quantitative result. Conway Pierce, a distinguished analytical chemist and ACS award winner, has remarked that he had serious doubts about the feasibility of putting quantitative work in the freshman laboratory, except in certain favorable instances (7). Chakrabarti has reported that in some universities which have tried integrating quantitative chemistry into the freshman laboratory the experiment apparently has failed, and should be abandoned (6). By way of conclusion, I wish to emphasize that no criticism of the teachers of sophomore and upper division quantitative analysis is intended or implied. Their subject is a demanding, necessary, and specialized branch of chemistry, and I do not envy their task of presenting it so as to preserve the interest and appreciation of their students. Nor do I blame them for trying to slough off the most dull, elementary, and uninspiring portions of their courses to the freshman level, while they themselves take off for the Elysian Fields of exotic new methods of instrumental analysis. I would probably do the same. But I think that the curricular revisionists of the freshman course who have fallen for this ploy should examine the effectsof their position on chemistry major enrollments. Robert I. Walter (8), reporting on a conference on the role of liberal arts colleges in chemical education, listed unsolved problems in the form of two brief questions 1) Haw can cbemktry be presented as an intellectual pursuit, rather than ss a. routine application of dull techniques? 2) How can the inspirational and motivational presentation of chemistry, particularly at the beginning level be improved?

As a brief partial answer, I would say-forget freshmen.

quant for

Mel Gorman

University of San Francisco San Francisco, California 94117 Literature Cited (1) Chem. En#. News. 48.22 (July 20, 1970). W. T., J. CHEW. EDUC.. 44,553 (1967). (2) LIPPINCOTT, D. A,, I. CAEX.E D U O . , 45, 419 (1908). W A L T E ~R. (3) DAVENPORT. , I., J. CXEX.EDOC.. 47, 183 (1970). G E ~ ~ K H.,EJR.. , J. CREW.EDOC.. 47.440 , - m ~7 m ~ ,. , . (4) LIPPMANN, D., AND YAoER, B., J. CREW. EDUC., 45. 749 (1968). (5) RONNEBERO, C.. Chem. Eno. News,48.50 (July20. 1970). (0) C n * n ~ * n * n ~C. ~ .L., J. CHEP.EDUO., 47.58 (1970). (7) PIEROE. C.. J. CREM.EDUO.. 43,456 (1900). (8) W * ~ = s n ,R . I.. "Advisom Council on Collwe Chemistry:' serial Publication No. 45.23 (Oot.1969). ~

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