The Function of General Chemistry'

I t is our duty, in turn, to imbue the next generation of young men with the understanding and spirit of re- search; and that, I believe, is the prime...
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The Function of General Chemistry'

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HUBERT N. ALYEA Princeton University, Princeton, New Jersey

E ARE chem~stsby profession because we are . .' expenmentahsts by nature, and because some years ago when we were students, our chemistry teachers wisely encouraged us in experimental research, and we liked it. I t is our duty, in turn, to imbue the next generation of young men with the understanding and spirit of research; and that, I believe, is the prime function of the general chemistry course. Let me be more specific about research. Some years ago I was curious about the reaction between hydrogen and oxygen. These two gases explode under certain conditions only a t low pressures. Why? Why does increasing which increases the number of molecules. decrease rate of reaction? How do the hydrogen and oxygen molecules interact? Why does packing the vessel with glass wool prevent explosion? Why does washing the vessel with a solution of potassium chloride retard the reaction? A thousand and one questions flooded my mirid, clamoring for answer. I had experienced the first stage in the life history of research: curiosity. There was but one way to find answers: to learn everything about hydrogen and oxygen. Into the chemistry library I went. I read hundreds of articles. I took copious notes. I became a storehouse of knowledge on the hydrogen-oxygen reaction. I became an authority. I had traversed the second stage of a research: fact-&ruling and the acquisition of knowledge. Finally I entered the last phase. I uncovered conflicting statements among the authorities. I discovered that often they knew less, but wrote more, than I. I took issue with their conclusions. I challenged their theories, and devised and carried out experiments testing whether their theories 6r mine were correct. In the end I experienced the glowing reward which comes from original research: I made discoveries. Now you all, as research chemists, have passed through these same three stages, culminating in the joy of discovery. And I maintain that the function of general chemistry is to give this same experience to the student. First, to arouse his curiosity. I t is our heritage. Our predecessors, the alchemists, certainly wondered. "Superstitious, often dishonest, . . . without this blind groper after the hidden mysteries of energy and matter, modern chemistrv would never have been born. I can see him now. working over his nots and retorts in crude laboratories and dark caves . . his imaginanon often fired with lofty real. exerrtrin~an almoit infinite y m r n r e as with the passionate purpose of a rcliwuui fanatic he sought to find ur m ~ k ethe Philu\uphcr's Stonr "2 Contribution t o a Symposium on the First Two Years of College Chemistry conducted by the Division of Chemical Education a t the 100th meeting of the A. C. S., Detroit, Michigan, September S 1 3 , 1940. DARROW, "The story of chemistry." Bobbs-Merrill Company. Indianapolis, Indiana, 1930. p. 2.

Now the march of time takes us forward three hundred years into a little apothecary shop in Goteborg, Sweden, a t the time of the American Revolution. The keeper of the shop is an ardent experimentalist, Carl Wilhelm Scheele. discoverer of chlorine. tun~sten. molybdenum, oxygen. Eking out a meager existence, struggling against ill health which struck him down at the early age of forty-four amidst a life of feverish activity, he writes: 0

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"Oh how happy I am. No care for eating or drinking or dwelling, no care for my pharmaceutical business, far that is mere play t o me. But to watch new phenamena-this is all my desire, and how glad is the enquirer when discovery rewards his diligence; then his heart rejoices."'

This love for fathoming the mysteries of natural phenomena was well phrased by Wilson, biographer of Sir Henry Cavendish, when he wrote: "His Theory of the Universe seems to have been that it cansisted solely of a multitude of objects which could be weighed, numbered, and measured; and the vocation to which he considered himself called was to weigh, number, and measure as many of those objects as his allotted three score years and ten would permit."'

It is difficult for us, as scientists, to realize that our students may not necessarily be enthusiastic about natural phenomena; and that our f i s t task is to stimulate their curiosity. Their natural sphere of appreciation may lie in the beauty of words, or in the harmony of music, or in the lovelinek of a piece of sculpture, architecture, or a painting. It is for us to divert their appreciation to the beauty of tmth. For truth is the god of our profession. Let us read what an artist says about us. .. ,,

"The scientists regard truth as the paiamount issue . . . they crave a meticulous precision of observation, measurement, and statement quite alien t o the other teachers of men. They exhibit an almost shocking insensibility to the cherished motives of belief. They do not ask whether what is sought is right or wrong, beautiful or ugly, useful or futile, comforting or distressing. They only ask whether what is found is an instance of something really happening." -

b d so our primary duty, as teachers, is to arouse the curiosity of the student in natural phenomena. Next he must learn facts. Mendeleeff writes: ."Refrain from illusions, insist on work and not an words. Patiently search divine and scientific truths."S

We must impress upon the student that he is working in the laboratory, which means he must labor; that the important discoveries of science are not plucked from SCHEELE, Letter to Gahn, 1775. WILSON,"Life and works of Cavendish," Harrison and Son. London, 1851, p. 186. MENDELEBB, M solution^," Demarkava, St. Petersburg, 1887, Preface. (In Russian.)

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the tree of knowledge like bunches of grapes, but painstakingly and laboriously dug up like potatoes or peanuts. Third, we must teach the student critical judgment. This includes a number of factors. It includes sensible and extensive application of the many principles taught him, interpretation of graphs, and correlation of data in tables and graphs. It includes, also, encouraging the student to disagree with the teacher, with the textbook, and with the laboratory manual in the light of his own observations. Hildebrand6 relates that his most satisfying research was carried out as a high-school student, wherein he disproved the statement of an eminent Hamard chemistry professor. That, I submit, is an excellent reommendation for the high-school teacher, who could so fortify his pupil in the exercising of critical judgment that he dared to disagree with a Harvard professor. The student must be taught the suspended judgment of the scientist, who decides temporarily, and will change if shown something better to change to. The student must understand that much he learns today may be different tomorrow, and different because of discoveries which he himself may make. Atomic structure, the concept of acids and bases, the theory of ionization : all will be altered for convenience. He must realize the suspended judgment of the scientist who says: "Say not this is the truth, hut so it seems to me l o be as I now see the thing I think I see."

The student who experiences the delight of exercising this critical judgment will need no coaxing to add to his fund of knowledge. He will realize readily that a firm foundation presages sound judgment. As Kekule related in his discovery of the ring structure of benzene as he sat dreamine before his fire~lace:

"But look! What was that? One of the snakes had seized hold of its own tail, and the form whirled mockingly before my eyes. As if by a flash of lightning, I awoke; and this time also I spend the rest of the night in working out the consequences of the hypothesis. Let us learn to dream, gentlemen, then perhaps we shall find the truth . . . but let us beware of publishing our dreams before they have been put to the proof by the waking understanding."i

The function, then, of general chemistry is: (1) to arouse curiosity (2) to implant knowledge (3) to cultivate judgment. The relative emphasis on these three items depends naturally upon the particular course and its relation to the subsequent program of the student. By electing the advanced general chemistry course, the student has already indicated his scientific bent and his stimulated curiosity, so that a fundamental training in advanced inorganic chemistry and the exercising of sound judgment is prescribed. On the other hand, for the beginner who will probably not continue in chemistry, curiosity and judgment are paramount; while knowledge is merely of transient importance. In either event we seek to duplicate for the students the experiences we ourselves have had in our own research. Then i t is that the students realize why we are fascinated by chemistry, why we cling to our profession, why we enjoy the laboratory despite the smells and smokes, filth and fumes, dirt and poverty; and, like the alchemist of old, with curiosity impelling us, with knowledge sustaining us, with criticism and discovery thrilling us, "among all these evils (we) seem to live so sweetly that (we should) die if we (should) +arife places with the Persian King."B - 6 ' JAPP, "Kekulh Memorial Lecture," J. Chem. Soc. (London), 73, 100 (1898). BECHE~, "Acta Laboratorii chymica monacensis, seu physica subterranea." 1669, Preface.