What's wrong with chemical education?

inventiveness, ability to analyze proposed projects deeply and accurately, to discriminate between essen- tials and trifles, to plan and execute, the ...
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WHAT'S WRONG with CHEMICAL EDUCATION?* HARDEN F. TAYLOR The Atlantic Coast Fisheries Company, New York City

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T IS a commonplace among industrial research directors and business executives who have had experience with research men, that getting a really good research chemist is a matter of luck. It is not difficult to find competent chemists who can prepare standard solutions and perform analytical and other routine work acceptably; but the qualifications of aresearchman-wide knowledge, aeative imagination and inventiveness, ability to analyze proposed projects deeply and accurately, to discriminate between essentials and trifles, to plan and execute, the qualifications of resourcefulness and persistence, and, finally, a balance between academic learning and practical busin e s s t b i s combination is a rare jewel, hard to find, and, I might add, somewhat more perishable than mineral gems, for a research genius sometimes loses the sparkle. That, however, is the problem of those of us who hire him. Your problem is how to produce him. I firmly believe that the most important single factor in turning out high-grade research chemists is expert teaching-with all due allowance for native ability of the students, the so-called "talent" of diierent students for certain subjects, and other circumstances that are convenient excuses and alibis. I believe that the teacher's job is to teach, rather than to conduct research and publish papers or attend conventions, important though these functions may be. To which you may shrewdly reply, "Quite so; but the teaching genius is as rare as the student genius, and equally as undefinable and unaccountable. Some teachers, like some students, are talented or gifted, have the spark of genius. Others do not." To this I reply that genius or talent or giftedness in both teacher and student is, to a large extent, susceptible of analysis, definition, control, and improvement. The three principal stages in a aeative research project are, usually, conception of the idea, theoretical analysis and planning of the project, and carrying it out to a practical conclusion. Corresponding to these three main steps are the three desirable attributes of the chemist who has the project in hand, namely, creativeness, theoretical insight, and practical skill and resourcefulness in adapting means to ends to bring the undertaking to a successful conclusion. The most valuable of these qualifications of a research chemist is imaginativeness or inventiveness, perhaps because it is rarest. Some chemists are highly -*Presented at a joint meeting of the Chemistry Teachers' Club and the New York Chapter of the American Institute of Chemists in New York City, January 12.1934.

creative, all the time bubbling over with new ideas, sometimes so rapidly and brilliantly that the ideas get in each other's way. Other chemists rarely or never conceive an important new idea. Is aeative imagination an innate talent or gift possessed by the lucky, and hopelessly beyond the reach of others? Or can it be inculcated in students, or developed in them by a skilful teaching? While I am not prepared to be categ&ical on this point, I believe that the matter is so important as to be worth the most serious study. The discovery that the imaginative faculty can be developed in students by skilful teaching would he the most important advance in education in many aday. Adissection of the creative process seems to indicate that creativeness can or ought to be capable of development. Ordinary creative imagination in the natural sciences seems to depend on two main essentials, the actual mental possession of a large number of concepts, and the mental habit of trying to fit them together to produce new combinations or ideas. The chemist's mind should be the warehouse in which is stored a large inventory of facts, concepts, bits of knowledge; the elements and their properties, factual and numerical data about them; the properties of their compounds, the mathematical laws governing their behavior. Included among these concepts, also, are queries, unsatisfied curiosity, problems, which can be solved or satisfied with appropriate facts. These are the pieces of jig-saw puzzles which, when fitted together, make a definite picture. The active and imaginative mind is as alert for these bits of new knowledge as the stamp collector is for new and rare stamps. The mental habit of trying to fit these bits of knowledge or concepts into new combinations is aeative imagination. That is, creative imagination of the ordinary kind such as we look for in chemists. This definition is, of course, a u d e and probably too simple for the real flights of greatness, such as that of Max Planck when he conceived the quantum theory, or Newton when he invented the calculus. I t follows that the bits of knowledge from which new ideas are generated must actually be in the chemist's head, not merely in reference books on the shelf where he can find them if he wants to look them up, for if one fact is on one page of a book on the shelf, and another fact on another page or in another book, and from these two facts, when fitted together, emerges something new and important, they will never come together unless they are both in the chemist's mind at the same time. The chemist would never look up either of

them in the books unless something in his mind suggested the relationship between them, and as long as neither of them is there, the relationship or idea is not very likely to occur to him. If, up to this point, our argument is correct, then hard drilling in the factual data of chemistry is the first essential in the teaching of chemistry. But the stuffing of the mind with fads, essential though it is, is not alone adequate to a creative imagination. The other part is the mental habit of piecing or fitting these facts together. To this end, the chemist must ever be playing around in his mind with the facts he has acquired. If he limits his chemistry to working hours or classroom hours and turns his mind thereafter to his home affairs, the football game, or his girl, he limits by so much his chances of fitting his store of facts into new combinations. Going to and from work, riding the subway, or when he is bored at the movies, his mind can be, within itself, fitting together the concepts he has. I t is excellent self-entertainment and an impregnable defense against boredom anywhere. Solitude for reflection seems to be highly important, if not essential, to the process. To illustrate from introspection: The chemist who has been working on problems of refrigeration is aware of the need of a perfect refrigerant gas, and of the properties needed in such a gassuitable boilmg point, high latent heat of evaporation, low specific heat of liquid, relatively high critical temperature, high degree of stability, non-inflammability, non-corrosiveness, non-toxicity, etc. Reading somewhere in Mellor he runs across sulfur hexafluoride and notices that it is very stable. Another inorganic g a s h o w interesting! A new bit of knowledge acquired. Will it fit into anything else? I wonder how it would fit in as a refrigerant gas, the unsatisfied demand already in his mind? He then eagerly searches the literature for every bit of information he can find about SF8. If he finds the properties to fit in with the requirements, he has generated a new and valuable idea. The requirements of refrigerants have been known for years and can be looked up in books. SF6 has been known since Moissan first made it in the 1890's. But the two sets of facts printed in books had never come together in anybody's mind in forty years. When the properties needed on the one hand existed in the chemist's mind, as soon as the substance entered that mind and the mind began to fit it in with other ideas already there--it clicked into place. The birth of an idea! Another case. Let us say SFs eventually did not work out (for most ideas turn out to be worthless). On another occasion the chemist happens to glance at a table of properties of the rare atmospheric gases. It is his habit always to be trying to fit every new fact into something he already knows. One by one he considers the properties of these gases. He comes to xenon. Absolutely inert. Critical temperature 58". A little low. Wouldn't it be wonderful if one of the absolutely inert gases of the air could be turned to use as a refrigerant, instead of the unstable, smelly, and often

dangerous organic compounds? Perhaps xenon does not fit in very well with his needs for a refrigerant, but a consideration of its properties may fit it in somewhere else. Or suppose our chemist is tussling with the problem of smoking hams or fish. He is out gunning to increase his store of knowledge about smoke. He reads about the heat decomposition of wood, and the composition of smoke and wood tar. He wonders about the effect of each constituent that comes to his attention-methyl alcohol, acetic acid, the cresols-he sees that formaldehyde is present in considerable quantity. What effect can this have? To mind comes Sikensen's form01 method for amino acids, the effect of rendering proteins insoluble and tough-why, formaldehyde is used for tanning white leathers! It can't be very good for meats. It will not only toughen but will destroy the flavorous amino acids. Now our chemist has tucked away somewhere in his mind an old fact that he has known for years, that ammonia combines with formaldehyde to make a neutral, inert, tasteless solid, hexamethylenetetramine. This old fact clicks into a perfect fit with the new facts about the effect of CH20 on meats. He injects ammonia in measured amount into the smoke, with an entirely new and very valuable result. Birth of a new idea! Now he goes farther. He spots pyrogallol among the constituents of smoke. A new bit of knowledge. He already knows that alkaliine pyrogallol is oxidized to a brown stuff that stains the photographer's fingers. Great! This is the coloring stuff in smoke. If we just put in enough more ammonia to neutralize the acetic acid and give a slight alkaline excess, we will get quick oxidation of pyrogallol and fix the color definitely and immediately. So, the new knowledge fits in with the old. Now he goes farther still. Wood smoke or tar is soluble in alkaliine solution but is precipitated by acids. Smoke is strongly acid. If the ammonia is added in slight excess it will not only promote oxidation of pyrogallol but will make the smoke soluble so that it can penetrate the ham. One idea right after another! Everyone of the facts which constituted the ideas was old and recorded in the literature for decades. Nothing is new but the combination of old facts. But as long as they were merely in the printed book they were embalmed and useless. Nothing could bring them together. Once they arrived in the brain of the chemist they were ready to click together as new and valuable and brilliant ideas. But even if the chemist has these ideas or bits of knowledge in his head they are still useless, unless he is actively busy fitting them together. This is the final and absolutely necessary act of imagination. We all have facts in our heads that are stuck perhaps within adjacent brain cells within a millionth of a millimeter of each other. When somebody else fits them together, we remark, "Well, for goodness sake, why didn't I think of that!" No doubt most of you have read the extraordinarily

etc.-and to figure them out from the pictures in the catalog. The student became intensely interested in the catalog, wrote an excellent paper, and, I dare say, still remembers some of the information gained thereby. Chemistry teachers might well consider as a challenge to their profession the possibility of developing imaginativeness by direct teaching methods. I believe that the chances favor a great improvement in the teaching of chemistry by the deliberate attempt to develop students to imaginativeness. Even if the attempt should fail, the effort still would be worth while in compelling the students to know more. Most chemists know too little about chemistry, and far too little about the content of other sciences. Once I was setting up a rather elaborate precision potentiometer for temperature measurements with a thermocouple. My assistant was a graduate in chemistry from one of the larger state universities, and a master of science in chemistry from another. I asked him to make a connection of two wires whiie I was adjusting something else. When the instrument failed to respond to a closed switch, I inspected the connection he had made. He had twisted the two ends together with the insulation on, and protested that I hadn't told him to scrape it off. This master of science in chemistry, with two beautiful Latm diplomas, did not seem to know that for electrical contact the bare metals must be brought together. We now come to the second important attribute of a good research chemist-what he does with his idea after he gets it. Here is one of the commonest weaknesses of chemists. Most people, chemists included, prefer working with their hands to working with their brains. As soon as the new idea is generated, and enthusiasm is all aglow and aquiver, the chemist usually humes into the laboratory, sets up apparatus, buys new equipment and reagents, and begins to work with his hands, before he has really started on the headwork. Science has gone so far, and natural laws have been so thoroughly codified, that it is often possible to work out the new idea completely on paper before any laboratory work is done, but chemists all too frequently insist on rediscovering the laws of nature for themselves. Let us take up our example of SF6 again. With the happy idea of using it for a refrigerant gas, the chemist, in a hurry to get going with some apparatus, may find where he can buy some SFs, or, failing that, he sets to work to synthesize it from sulfur and fluorine so that he will have some of it to work with. Then, perhaps, he begins to measure its boiling points, or devises a pump in which to experiment with it as an actual refrigerant. This work is all premature. If, instead of beginning the experiment right away, he sits down at his desk and begins a systematic examination of his idea from the theoretical point of view he will progress more rapidly and more surely. First, he looks up what numerical data he can find. Let us say, he finds the boiling and freezing points a t given pressures. He knows the mo* P L ~ T TW. , m B m x , R. A , "The relation of the scientific lecular weight from the formula and, incidentally, he should not have to look up the atomic weight of either . 8, 1969 (Oct., 1931). 'hunch' to research," J. C ~ E MEouc.,

interesting paper by matt and Baker on the scientific hunch.' I fancy that the arrival of the hunch, which is such a thrilliig event in the chemist's life, isnothing more than the clicking of two concepts in the chemist's mind. All of the circumstances described by Professor Baker as favorable to the hunch-solitude, reflection, toying with the problem--are also favorable to the collision of two bits of mental property. So, you see, the processes of creative imagination are not so mysterious, after all. Why can't we teach it or develop it? Perhaps we can. The student's mind must be charged with a large'amount of knowledge, not in reference books, convenient and available, but adually in the cells of his brain. It must be so firmly embedded in the mind that it sticks and does not promptly leak out. Perhaps we have gone too far in codifying scientific data in Chemical Abstracts, I. C. T., and Smithsonian Tables. These are excellent and necessary conveniences to research nowadays, but the student should not be allowed to think that he can be a creative chemist if he merely knows how to look up things in the indexes and card catalogs. He must know an enormous number of facts, and the teacher's job is by Spartan force to make h i get them and get them so they will stay. This part of the job we all admit can be done. But how to induce in the student the other essential, the habit of playing around with the bits of knowledge he has and attempting to put them together? Here is the real problem of developing imagination. Perhaps it will be sufficient to pose questions and problems, to make the student want to thimk up new things, and to commend and encourage him when he does. The thrii of new ideas is pleasant, so that a few experiences of the young creator should make h i strive to have more of them. This question can be left to teachers as a problem to be solved, of which perhaps more than one solution can be found. The student must acquire habits of omnivorous reading, for new jig-saw pieces are acquired this way. Reading should not be confined to matter all of which the student can understand. About half of what he reads may well be over his head. I t will raise questions which are beyond him a t the time, but into which new fads will later fit. Readmg, moreover, should not be confined to the narrow subject of the chemist's specialty, but should covermany fields of science, including always the titles, at least, of papers presented at the learned societies. It often happens that the idea taken from medicine or astronomy or geology may fit in perfectly with something in the chemical laboratory. In high-school teaching, I used to assign occasional extra tasks as penalties or to occupy a student who was getting ahead of the class. One day I had to think up an assignment quickly. An Eimer and Amend catalog lay on my desk. I handed the catalog to the student and told him to write me an essay on all the ways he could find of measuring diierent quantities-length, mass, time, specific gravity, temperature,

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sulfur or fluorine to get the molecular weight. If he does, he is inadequately trained. How many of its properties can he determine from these given fads? Indeed, what facts must be known in order to decide whether it is a suitable refrigerant or not? Well, from the molecular weight he knows the gas density (and should not have to look this up in a book), and from that he can calculate how much gas would be handled by each stroke of the compressor. From Trouton's rule he can compute the molecular heat of vaporization. From the Gnldberg-Guy law he can approximate the critical temperature as 1.5 times the boiling-point temperature. He needs to know the value of C,/C. or the ratio of the heat capacity of the gas a t constant pressure to that at constant volume, and he can get C, if he knows C, by subtracting 1.986 calories. And so on. He soon finds himself buried in the thermodynamics of gases and confronted with the interesting question: "What elemental facts must be known as a basis for calculating all of the others, what are the formulas for their calculation, and which of the elemental facts have not yet been determined?" By settling these questions, he avoids rediscovering the laws and fads that have already been discovered before h i by others. The chances are that he will find his idea exploded by calculations he can make from the already known data. If so, he has avoided the waste 0: time and the expense of experimentation, but if not, he then proceeds to plan the minimum essential facts that he must determine experimentally so that he can compute the remainder. Before doing this he must make sure that the work has not been done before, or patentdd, for the time to search the literature and patent records is usually before the laboratory work has been done. If, as often happens, the idea falls down under theoretical examination, before any experimental work has been done, the project has been enormously worth while nevertheless, because in the critical examination of his project he has gone over again, under conditions of vivid interest, an important section of physical chemistry which he went over perfunctorily and uninterestedly in college and promptly forgot, or has acquired new knowledge to which he had no previous access. Even though his idea is a failure, his value as a research man is vastly increased because he expanded his knowledge and grasp of chemistry and physics in the critical study he made of the idea. It is difficult to say, therefore, whether this thorough preliminary theoretical study of projects is more valuable in expanding the knowledge and value of the man or in preventing umecessary and costly experiment. But since it has both effects, it should be a sine qua non of research; unfortunately, it is not. In fact, it seems to be a rarity. Another illustration, taken again from thermodynamics. A few years ago, I was reading casually about the Peltier effect-the thermoelectric effect of junctions of dissimilar metals, used in thermocouples, whereby heat may be directly converted into electricity or oue versa. It appeared that some experimenter had

frozen a drop of water at the junction of bars of bismuth and antimony by driving an electric current through it. If a drop of water can be frozen, why not a ton, without any moving parts? So I began to read everything I could 6nd about the Peltier effect, the Joule-Thomson effect, and other relations between heat and electric energy. I found that if I had available all the current used in propelling the New York subway trains, to pass through a very low resistance, I could produce refrigeration. The projed failed, and I did no experiments, but I learned about the Peltier effect, including a number of very interesting thmgs I never knew before. There is a brief note in Science, by an anatomist, which describes a process of decalcifying bone for microtome sectioning without acids, by using a solution of a soluble magnesium salt, such as the citrate. Tricalcium phosphate soluble in neutral or alkaline magnesium solutions? Where does this f a d fit? What use can be made of it? Perhaps, we can think of no use just now. Clip out the note and paste it in the scrap book, some day I may need to know just this. Perhaps a year later the matter of calcium and phosphorus assimilation from the soil by plants brings out the old idea from the clipping. Can magnesium in the soil promote the availability of tricalcium phosphate? Does the Mg in sea water hold the calcium phosphate in solution and available for the hard structures of living things? A theoretical study of mutual solubilities will expand the student's knowledge even if he cannot directly profit by his effort. Project after projed, idea after idea is generated. Most of them are failures, but each expands the chemist's knowledge and usefulness, and if this habit is kept up, he rapidly grows in scientific stature. If ideas are numerous and each is analyzed thoroughly, a natural will occasionally come along which will reward the chemist abundantly and perhaps earn for him a wide reputation. The somewhat contemptuous attitude of practical people for what they call theory as opposed to practice is perhaps related more or less closely to the proneness of researchers to plunge into experiments on a little, but not enough, theory. Theory and practice, of course, should agree always; if they fail to do so it is often because of faulty theory, or insufliciently comprehensive theory. The young chemist may feel that he should not let theory run away with him; nevertheless the highest type of research is that which is guided by theory, of which there is too little rather than too much. Research that is not governed by well thought out theory is necessarily of a low order and usually of relatively slight value. On reading what I have written up to this point, it appears that perhaps I have been describing merely one style or policy of research-one that I happen to like. But what if the chemist is assigned a pressing problem, and there just aren't any ideas? Or, where the materials are complex mixtures, such as milk, or wood, or meat, which are beyond known exad laws? Here, of

course, systematic empiricism is the only method possible--the method of holding all factors but one constant and varying one at a time until the optimum results (sought) are obtained, whatever they may be. This involves little, if any, creative imagination, and little theoretical analysis, though perhaps good technic and enormous patience. Students should, however, clearly understand this mode of attack on problems, and when it must be used. The third attribute that may be desirable in research chemists is that they be practical. If they are to go in for pure science this attribute is of no significance; if they are to devote themselves t o applied research a practical viewpoint is highly desirable if not essential. After all, this is principally the responsibility of those of us who hue them rather than of their teachers, except in courses in industrial or applied chemistry. Practicality is nothing much more than the ability to discern and apply the limitations of expense in business, to make the process sufficiently rugged and simple to be operated by ordinary workmen, and t o resist the temptation to mix up interesting academic questions with the rather stern and sometimes prosaic demands of business and industry. Interesting and important academic or theoretical questions are constantly arising in industrial laboratories to tempt the researchers away from pressing problems. At the same time, teachers of graduate courses are sometimes put to it to think of good research projects for their advanced students. Why not arrange a service whereby the industrial laboratories could transmit to the colleges the important academic questions that arise? A few years ago we were in great need of a really precise method for determining fluorine. The published methods could not determine this element in sufficientlysmall quantities. The project was dropped. Why should not such problems be referred to college laboratories to be attacked by advanced students? In this field of practical research it is important to note that a well-balanced combination in one person of all three attributes mentioned-imaginativeness, thoroughness in theoretical analysis, and practical skill in carrying out the project-may be difficult to maintain. A highly developed imagination may generate ideas of such frequency and luster that the researcher who generates them is unable to concentrate on the analysis or development of any of them. While he is trying to work out one idea, it begins to become stale, while new and fascinating ones come in for attention. Such researchers come to live for the daily thrill of a new thought, and are satisfied with these thrills without the satisfaction of solid accomplishment. They are prodigal in giving them away, for they come to feel that plenty more ideas are on their way. Perhaps teaching can do nothing to overcome this difficulty. Nevertheless, give us the man with ideas, even if he is unable to carry them out. In a properly organized industrial laboratory it is always possible to get competent plodders to carry out the brilliant fellow's ideas.

It would be presumptuous of me to venture, with my exceedingly limited teaching experience, to discuss the actual technic of teaching with accomplished people who make teaching their daily work. But possibly here, too, some mysteries, suchas talent or gift for any particular subject, may be analyzable with profit. Are some students naturally bent for chemistry, others not? Can we not explain such well-known phenomena somewhat as follows? A class of forty students begins on the same day in a course of chemistry. The course itself is arranged in logical order, each subject depending to some extent on what has gone before. Now, if thirty-five of the students really get all the subject matter of each assignment from the first day, the subject of chemistry soon begins to be understandable, vivid, interesting. They feel that they are going somewhere, and accomplishing something. But the other five did not, from the very beginning, get it allperhaps only very little, or none. The teacher does not detect this lag promptly, but, for one cause or another, permits, say, a month to pass before realizing that these five are not doing well. He then begins to apply pressure and make demands for better performance. The students perk up and try a little harder-at the place in the course where the class now is. They miss the point entirely by not going back to the beginning, if that is possible, and laying the foundation which they failed to lay with the rest of the class. That is difficult and unlikely of success, and if attempted the thirty-five will still go on ahead of them. Under pressure they are unhappy and begin to be resentful or decide they have no talent for chemistry, dislike the smells, the teacher, and everything about chemistry, and will probably carry this belief throughout life. If I have correctly analyzed the case, it was not talent that was missing, but diligent effort from the very start, and a laying of the foundation. At least, that accords with my observation. Now, if this is true, then the most important part in a course is the first two or three weeks, to get every student started right. Take this, if you must, as a gentle intimation that the missing talent may be the teacher's fault. To carry this thought a bit further: if students are rated in grades, say percentage marks, these marks are supposed to express the ability or accomplishment of the students. Why do they not also represent the proficiency of the teacher? If I assign a grade of 80% to a student, might I not say to myself, secretly, perhaps, that I was a 20% flunk on that student, and if I flunk the student, do I not also flunk myself as a teacher? To summarize, then: chemistry students do not know enough. They need to know more facts, to hold them in their heads rather than to know where they can be found and how to find them if they are wanted, so that they .may be the raw material for new ideas. Chemists need to acquire the mental habit of fitting these ideas together, of cogitating the facts, turning them over and playing with them mentally, encouraging

new ideas to pop out of them. Chemists need to know more of the codified laws of their science, and of natural sciences generally, mathematical and otherwise. These generalizations are necessary to proper analysis of an idea before experimental work is done on it. Chemists need to make, as a matter of course, thorough theoretical analysis of their problems, and to aim a t the ideal piece of research which can occasionally he achieved, as the complete job done on paper with no experimental work except physical verification or demonstration. As

science advances and natural laws are extended in more and more detail, this purely theoretical method becomes more and more possible, and applicable to more and more problems. Indeed, if a flight of imagination is here permissible, why may we not look forward to the time when, given a set of properties that are required for a substance, the chemist may sit down a t his desk and design a molecule that will have this combination of properties, as the engineer designs a machine to do the things he wants it to do?