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NEW ENGLAND ASSOCIATION of CHEMISTRY TEACAERS This Nation Will Need More Chemists , after the War ERNST A. HAUSERL Massachlcsetta Institute of Technology, Cambridge, Masaachtmettx
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HAT struck me most when I began to acquaint the study of medicine, biology, metallurgy, or ceramics, myself with the subjects taught in our high just to give a few examples. However, this is possible schools was the fact that chemistry is an elective sub- only if chemistry is a compulsory subject, since otherject; in most European countries it is compulsory. wise this chance would be missed by all who did not Could it not be made compulsory here too? I am not select the subject voluntarily. The next, equally serious problem is time. I n most basing this on any prejudice I might have, being a chemist myself, but on a number of reasons. I n these high schools chemistry is taught for only one year. times fundamental knowledge of chemistry and physics Assuming three recitation hours a week, one hour of should be as much a part of a general education as any lab work,and a school year of 40 weeks, the time allotted other compulsory subject. We can no longer deny to chemistry in a whole year amounts to 160 hours. If that we are living in a chemical age and that therefore one looks a t this figure and then looks a t the better a t least a knowledge of basic chemistry is as important known chemistry textbooks used in high schools tofor the general education of an individual as medieval day, one begins to wonder, and, if one is good natured, history, if not much more so. Furthermore, there can to pity the student. What I consider imperative therefore is the adjustbe no question but that a well-outlined course in chemistry will serve admirably to aid in training the student ment of the subject matter to the time allotted to it. in clear and logical thinking and reasoning. This will Probably the ideal solution would be to offer two types be of great value even to those who do not intend to of chemistry courses in high school. One would be taken by those who have shown no special aptitude in continue with chemistry in college. The chemical industry will need an increasing number mathematics and have lacked interest in their previous of workmen. There can be no doubt that a person who science courses, as well as those who explicitly expressed is at least familiar with what chemistry stands for, and disinterest in specialized chemistry. Such a course who has a t least a basic conception of chemical reac- should cover nothing but the fundamentals which tions, will approach his job with a greater interest every citizen should know as part of his general educathan one who has not the faintest idea what it is all tion. The other course, to be given to those who demonstrated their interest in natural sciences and proved about. However, the most important point I can see a t pres- their proficiency in mathematics, could then proceed ent is this: The tremendous impetus which the more rapidly than now possible and thus cover a more chemical industry is receiving through this war is bound comprehensive field. However, we all know that the to result in a considerable expansion in the postwar realization of such an ideal condition is rather problemperiod. This will necessitate the training of increasing atical, a t least for the present, and since there are a numbers of well-qualified chemists. Many a boy or number of other reasons which now would make i t girl, who for one reason or another has no specific impractical to increase the time allotted to chemistry, interest in chemistry a t the time of selecting courses, i t becomes essential to make the best of the situation. might very well be influenced to make chemistry his or This means, in my opinion, teaching chemistry in such her profession if given a chance to learn what i t is all a way that the student's interest in the subject is about, its importance in our daily lives, and its impor- aroused from the very first minute in class and is kept tance to the well-being of the nation as a whole. And a t top level throughout the year. The goal to be chemistry is also of importance to those contemplating achieved is not a student into whose head a conglomerate of high-sounding terms. recent theories. and results Condensation of an address presented at the Fifth Summer Of recentdevelopments been densely packed, but Conference of the New England Assodatian of Chemistry a young man or girl whose interest in chemistry has been Teachers, Andover, Massachusetts, August 27. 1913. .513
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stimulated and who has been given a chance to learn and master the fundamentals of chemical reactions in as illustrative and simple a way as possible. I know of no better slogan to illustrate what high-school chemistry should accomplish than Kipling's "I keep six honest serving men (They taught me all I knew). Their names are What and W h y and When And How and Where and Who."
Too frequently one overlooks the fact that the fundamentals of chemistry, if they are to stick, need more than learning by memory a few laws or symbols, or even equations; i t is necessary to train our brains to think in chemical terms. Such training, however, calls for simplicity, patience, and enthusiasm. Since one of the most important virtues of a chemist is logical reasoning, coupled with a keen sense of ohsewation, the need for experimental demonstrations cannot be overemphasized... A frequent reaction to this point of view is to draw attention to the limited budget, the lack of laboratory space, and the lack of time of the chemistry teacher to prepare demonstrations. Only the last of these three criticisms is serious. The chemistry teacher must have his time schedule so arranged that be can set up his demonstrations just ahead of his class. Although I personally am very much in favor of seeing every high school in our country eventually equipped with a simple but complete laboratory, this does not mean that we cannot carry out all really necessary demonstrations with a minimum of equipment and expense. If we had had to wait, for example, for today's accomplishments of the glass industry, the ceramic industry, metallurgy, etc., to carry out experiments which have led us to the fundamental concepts of chemistry, this science would not yet have been born. Let me be more specific. I consider i t a serious mistake to force the young student who has been barely exposed to chemistry to learn the teachings of the electron theory before he has even acquired the most fundamental knowledge of chemical reactions. In the year the student is first introduced to chemistry his brain is certainly not trained to deal with abstracta. He is far more impressed by Samuel John Stone's famous expression, "What I cannot see I never will believe in." The net result therefore is that he either does not understand the meaning of a nucleus surrounded by electron orbits drawn on the blackboard and becomes utterly disgusted with chemistry and himself, or he takes everything for granted instead of realizing that this complex theory actually is a working hypothesis which so far explains most chemical phenomena admittedly better than those of former days. However, what is overlooked too frequently is the fact that a real understanding and the ability to apply intelligently these new concepts call for the knowledge of many basic and experimentally proved facts. I do not deny that the juggling of electrons on the blackboard may be fascinating to a stndent who loves to dabble with
concepts daddy does not know about, but, lacking the basis for such a concept, a logically reasoning student will ask the famous question, "Why ?" And what would be your answer? When most of us went to school we learned, for example, and had it experimentally demonstrated, that calcium chloride results from the combination of two atoms of chlorine and one atom of calcium.*,Since it had been shown by previous demonstrations that the chlorine atom is monovalent, it was evident that the calcium atom was divalent. Such teachings were sufficient to turn out renowned chemists. Why then must the high-school stndent of today, who possibly might not even select chemistry for his lie's profession, strain his brains to memorize that the chlorine atom supposedly consists of a nucleus with 17 protons and 18 neutrons and a total of 17 electrons, and the calcium atom has a nucleus of 20 protons and 20 neutrons and a total of 21 electrons? Even if he is not compelled to memorize all this, he is unable to work out a simple reaction without looking in his textbook to find out how the reacting atoms are organized. But even if he is a wizard and does remember the composition of the atom in terms of protons, neutrons, and electrons, this is in my opinion still equivalent to some one who chews a lollypop before he eats his poached eggs for breakfast. However, this is not even enough; he also must remember that calcium can transfer electrons whereas chlorine must borrow some. Is it not far more important for him to know the composition of a calcium chloride molecule, how it can be produced, and to what uses it can he put, than to become an expert in electron distribution? Experience has shown that the time available for the teaching of chemistry in high schools is insufficient to do justice to both these aspects. Is it not also far more important for the high-school graduate who has had one year of chemistry to have some fundamental idea of the weight relationships, the gas laws, valences, a sense of orders of magnitude, a full nnderstanding of what acids, bases, and salts are, and so forth, than to be taught that colloids are noncrystalline substances which form watery or jelly-like suspensions with water, or to he told that the addition of protective colloids aids in the digestion of foods, such as the addition of gelatin to ice cream, or that the creaming of milk is due to electrorepulsion of colloidal particles? Needless to say, every one of these statements, taken a t random from the latest editions of recent high-school chemistry texts, is not only misleading, but definitely wrong. Being a colloid chemist, I am admittedly particularly interested in any chapter dealing with colloids. What strikes me most is the undeniable fact that the Cottrel process of smoke precipitation is played up in every book, seemingly because Cottrell is an American. Having been actively engaged with this process, I am the last one to belittle the ingenuity of the man or the process. But why give the student just this example, the mechanism of which he simply cannot understand with the knowledge of chemistry
and physics he has acquired up to then? This seems just about as far fetched to me as if I should demonstrate to the student the precipitationof barium sulfate from a solution of barium chloride to which in one case a solution of sodium sulfate and in the other a solution of potassium sulfate is added, and then ask him why in the latter case the supernatant liquid is alkaline and in the former acid. If colloids have to be discussed a t all in high-school chemistry--and I personally don't think they should be-then more appropriate examples could be selected which can also claim Americans as their discoverers, and which would a t least give the student a somewhat more correct idea of what we mean by colloids. Since colloid chemistry does not deal with a special group of substances, but with a special state of matter, i t is logical that it can only he of value to an individual who has covered inorganic and organic chemistry, as well as physical chemistry in a t least fundamental courses. That the Debye-Hikkel theory is now even being considered as a topic of discussion in some high-school chemistry courses is so fantastic that I do not intend to consider i t seriously. One might compare the student who is exposed to such things to a little child about eight years old who is taken to the theater to attend a performance of one of Shakespeare's plays. If this child should understand anythihg, and-enjoy the performance, I could only say, with Winston Churchill, "Some child!" The average child would not only be bored, hut very probably such an experience would make him lose interest in serious theatrical plays. These are just a few examples which could be multiplied many times but should suffice to point out the main objectiou I am raising against the present way of creating the interest of young people in chemistry and supplying the nation with the chemists i t will need. As previously stated, I consider it doubtful if an increase in the hours which can be devoted to chemistry in high school is possible or even advisable. Taking therefore the time as a constant, we must-if we stay objectiveadmit that the time available is entirely insufficient to cover the ground outlined in the present textbooks and achieve satisfactory results from a pedagogic point of view. Therefore, there remains but one solution: namely, to revise the courses and eliminate so much that what is left can be taught thoroughly and for keeps. What should he cut out is a matter for people more competent than I to decide. Personally, however, I feel that no harm but considerable benefit would result in eliminating the modem concepts of the electron theory, with a11 its ramifications, a t least during the starting period of the course, discarding everything on crystal structures as obtained by x-ray diffraction, or even more so, electron diffraction, not even to mention the electron microscope and to forget the unfortunate attempts to explain colloidal phenomena. In doing this we will not only win valuable time but we will also prevent the student from be-
coming unduly confused and consequently disgusted before he has a chance to realize what it is all about. We must teach chemistry in such a way that the suhject is not only fascinating and clear, but simple. In this connection I feel very strongly that far too much time is spent on the why of chemical reactions and far too little on the how. My reason for this is simple. If by showing or explaining to a student thehow, we make him curious and interested, he certainly will look for the why as he continues deeper into the subject. But in preparing a young citizen to become a valuable member of our profession we must do more than simply teach him symbols, formulas, and equations. We must not neglect the training of his hrain in logical thinking and logical reasoning. Chemistry without this is of no value. At this point it is time for me to digress for a moment to another science which in my opinion also deserves some readjustment. One of the fundamental tools of the chemist is mathematics. I have therefore also been interested in following the methods of teaching this subject. It is my point of view that if, for example, algebra and geometry are taught simply as the mechanics of numbers, they are not mathematics. Mathematics must be a process of thinking; if mathematics is taurrht as I see it, the chemist^ student will not only be able to write formulas into'his notebook, but he will immediately comprehend their full meaning. This naturally means that a change in the chemistry course alone is not yet sufficient and that close cooperation with the courses in mathematics is essential for full success. I have been told by a number of high-school teachers that children of refugees from central Europe, who had some schooling over there prior to their departure, have proved superior in their understanding of basic chemistry. These teachers expressed the opinion that this was due to a better training in mathematical thinking, and I agree with this point of view from my own experience. I am convinced that the chemical industries of the United States will undergo considerable expansion, therefore the nation will need more chemists than ever. And to maintain a leading role we need good chemists! Just as there is no value in building a house equipped with the latest installations but on a weak foundation, so it would be unwise to build a chemist who is full of the latest theories but lacking in the necessary foundation. To build chemists as sound, simple, and strong as possible is our job. That must be our contribution to our nation's future! I am greatly indebted to Professors Earl B. Millard, Arthur R. Davis, and George G. Marvin, of the Massachusetts Institute of Technology, Mr. Theodore Browne of the Dewey and Almy Chemical Company, and Mr. John Hodges of the Browne and Nichols School for their valuable suggestions and criticism.
