Values in chemistry - Journal of Chemical Education (ACS Publications)

It is necessary to remind students and ourselves of the essentiality of scientific values, particularly in chemistry. Keywords (Audience):. High Schoo...
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W. F. Libby University of California LOS Angeles 90024

Values in Chemistry

O u r society may hc forgetting the values of science. A major part of our high school and college graduates appear to have had little contact with it and little opportunity to learn about it, and worse still, in many cases seem to have developed an aversion, a kind of antagonistic feeling toward it. It is necessary, thercfore, to remind ourselves of the essentiality of the scientific values. And I would like to speak particularly of those in chemistry, my own field. Present Chemical Valuer

Wherever one turns in a fully developed country today, the chemist and his contributions are in evidence. Clothing, for example, is becoming largely synthetic, with even the dyes and the sizing synthetic chemicals. Many of the natural textile products still are superior to the synthetics, hut the synthetics are rapidly catching up, and we can foresee the continually increasing role of synthetic fibers and synthetic cloth. The food we eat is in many ways a chemical product. The preservatives, the artificial colors, even the processing, and certainly the sprays and disinfectants, the fertilizers used in the production, all make farming and the preservation and processing of food a chemical business. Pharmaceuticals, of course, constitute a major chemical contribution. The miracle drugs, and even the not so miraculous drugs such as aspirin, bring us to perhaps the most important of all the areas of chemistry, a t least in promise for future development, biochemistry. The contraceptive pill, of course, is one of the great developments of this century. Possible Future Values of Chemistry Chemicol Control of Heredity

Biochemistry and molecular biology are largely chemical in cast and substance. The fantastic story of the unraveling of the deoxyribonucleic acid (DNA) structure has brought home to many of us, in a most dramatic way, the great importance of understanding the detailed chemical structure and behavior of the basic units out of which our bodies arc constructed. Nothing offers more promise for our future than the understanding and development and revelation of the chimical basis of heredity. There may well he a day when genetic changes can he made at will by chemical treatment. Contribution from the California Association of Chemistry Teachers. 190

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Artificial Photosynthesis

We've learned about the chemical processes by which green plants grow. Incredibly complicated as they are, they are beautifully designed and efficient. Here again when we've fully understood them, there undoubtedly will be tremendous practical applications in raising the photosynthetic efficiency to even higher levels than nature achieves. Dmgs and Control of Mentol Processes and Illnesses

We begin faintly, but just barely, to see our way through the psychological effects of chemicals. This never-never land is one still laden with witchcraft and non-scientific lore, hut it begins to clarify, and it looks as though we can dream of the day justifiably when some of our most grievous mental illnesses will be curable. I n fact, today, miraculous cures like this already exist. Control of Aging and Generol Promise of Biochemistry

It seems possible that our understanding of the deterioration of tissue may lead us to the protection of our substance from aging. And we may come eventually to live as long as Methuselah. These are dreami n g ~of the future hut conceivable possibilities. These four are in biochemistry and molecular biology which me cite first because the field is so rich. In fact present accomplishments in these areas probably have been minor as compared to those lying ahead in the future, although these in themselves have been fantastic. I t is only one century since the first antiseptic was discovered by Pastcur and Lister; only one century since man could protect himself against infections in wounds which broke the skin; only one century since the principle of antisepsis and antitoxins arrived. In one brief century we've come a long way toward freeing ourselves from dread diseases and scourges. Many remain still to he conquered, but my point is that the future promise is so enormous that great as these past achievements have been they probably will be exceeded greatly by future applications. New Moteriols

New materials, the invention and development of new substances, new matter through chemical techniques and knowledge is a fantastic new area of chemistry. I n some instances it may he a hit borderlink as to whether the new product is really entirely chemical in origin or has been mechanically engineered. I refer, for instance, particularly to the fiber reinforced plastics which promise to revolutionize aeronautics by reducing the

weights of airplanes and space ships. Fibers properly implanted in plastics and glasses make them so strong that they rival all other materials in their strength and of course weigh far less. New Bmnches in Chemistry

From experience in the space program as in atomic energy before it, we have learned with no surprise that chemistry is vitally important here also. And in the course of this we have come to realize that the space program has its significance for chemistry also in dramatic new branches in chemistry. Once man leaves the surface of the earth the environment changes. If he goes downward he comes to pressures which in the very center of the earth is 3.3 X 106 atm. If he goes outwards he comes to a vacuum so extremely empty that nothing on the earth approaches it. And, of course, if he approaches the sun and the stars, temperatures far above anything attainable on earth are incurred. I speak of the development of the chemistry of these areas as being promising for the future technology in our society and holding benefits which may be, though inestimable, of very great value. Chemical Value of the Vacuum of Space. In our laboratories at UCLA we are attempting to use the inexhaustibility of the vacuum of space for chemical purposes. Air is a vicious chemical. We believe dramatic improvements and accomplishments may be possible-if certain chemical processes were freed of air. So we are trying hard to free our equipment of air by putting it in one of the large space chambers which were developed for the testing of space ships (since leaks and out-gassing are properties of the surface of the vessel containing the vacuum, increase of the size of the vessel reduces the relative importance of these ever-present enemies of a high vacuum when measured on a unit volume basis). The large chambers cannot readily he contaminated since their pumps are so enormous and their bulk so great that the amount of air required to damage the vacuum is far greater relative to the speed of the pumps than in smaller equipment. And thus we hope to develop the technique of the distillation of carbon onto diamond surfaces and thus establish a process of growing large diamonds. We also are trying to produce ductile beryllium by the distillation of beryllium in the vacuum. This mould seem to be an excellent possibility as it seems most likely that the fragility of beryllium and its brittleness may be due to oxide impurity. However, whether these examples work or not it would seem clear that the capability of producing materials free of oxygen and nitrogen and other gases should he a substantial asset to the chemical industry and may make space chambers or even orbiting satellites valuable as chemical factories. High Pressure Chemistry. Similarly in the field of high pressures, the chemical effects of pressures of a million atmospheres have hardly been thought about. However, chemical effects of pressures of 10,000 atm have been widely studied and are dramatic in value. The first process for the production of polyethylene was a high pressure process using some 2000 atm to force the ethylene to fit into the growing polymer, and it is nothing derogatory against the high pressure process that catalysts were developed later by Ziegler and Xatta

which allow the polyethylene to be made at low pressures. Pressure causes matter to transform and to change its properties. Thus we think it not unlikely that at the center of the earth iron may have significantly different chemical properties. We're quite certain that lighter atoms, such as hydrogen, mould indeed be transformed and in fact would he metallic. We can predict with some confidence,that light elements under pressures of 3 X lo8atm mould be metallic, and that at higher pressures still all forms of matter would become metallic. As we continue to compress matter we finally obtain densities like those in some stars. For example, the white companion of the star Sirius apparently has a density about lo6times that of water. We have never experimented with this form of matter because we have no equipment for producing it. Yet it is not at all clear that this is impossible. If me could reach what might he called this Fifth State of Matter (the other four being: solid, liquid, gas, and plasma) we undoubtedly would open a whole new world of chemical reactions. Explosive shock, for instance, may throw matter temporarily into this super-state from which it may fall out after the shock wave passes, and this might leave the atoms in a different form-a different molecular combination. Thus it has been proposed that the explanation of the fact that diamond can be produced from graphite explosively is indeed due to such a transitory sojourn in the Fifth State of carbon. This is just a theory, hut it might even be true. We have as yet only minimal effort in the chemistry of extremely high pressures, a very rich and promising area for the chemistry of the future. High Temperature Chemistry. Similarly, high temperature chemistry, though it has been investigated over many decades with some very fine accomplished results, is an area so vast that it seems to me fair to say that the promise of the field still is enormously greater than is generally realized, especially with modern techniques such as radio frequency power sources. With these devices it apparently is possible to attain essentially any temperature up to many tens of thousands of degrees in a gaseous plasma flame which then can he used to heat other objects as well as to react itself to produce new molecules. High current arcs are nearly equally effective methods of obtaining matter at such extreme temperatures. Such techniques now allow routine work a t 5000°K and above. But there are relatively few chemists working in the area and very few applications have been made industrially. It certainly is an area of great importance for the future. Chemical Theory wzth Computers. Turning in a different direction, we speak of chemical theory. For fifty years now we have been possessed of a theory of the hydrogen atom, and for the same fifty years have strained trying to apply that simple theory to more complicated atoms and not doing well a t it. The advent of the large computer, however, makes this task now much more practical, and I venture to suggest that the availability of large computers will give us an atomic theory which will extend up to the imporlaul element carbon and possibly even beyond. With this then we may find that me can do carbon chemistry accurately Volume 46, Number 4, April 1969

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theoretically. This may prove to be of fantastic significance for biology and all that turns on organic molecules and their behavior. It would seem that we are on the verge of such a breakthrough now. It is likely that it will be some time before the technique is sufficiently widespread and enough chemists have been educated in its use to have major impact on the average research, but it seems likely to come. Management i n Full Light of Chemical Knowledge and Understanding. Every single technical program, whether it be primarily chemical in nature or.not, such as atomic weapons and atomic energy on the one hand or the space program on the other, owe enormous debts t o chemistry. Not the least of the contributions is the chemical leadership given by men like Dr. Reaborg, Dr. Hornig, and Dr. Kistiakowsky in guiding these programs. (All of these distinguished gentlemen are chemists of the first rank.) Many of the largest corporations have chemists in high positions although they are not primarily chemical companies. The broad knowledge essential to a chemical career is a major asset in technical management problems. The Means

All of this will come about only if students in the high schools and in the colleges believe and are excited by the problems and possible discoveries and opportunities. Only if they come to rank these with other great adventures, and want to join in the attack; only if these things are true will our chemical future be a bright one. It seems to me, in short, that we must do everything

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to assure this. When enrollments in our sciences falter, we should do everything to assure that they rise to the necessary level. Totalitarian societies have an advantage in this respect which me must be careful ~ i o to t forget. Scientists have a way of talking to one another and not to the public in general and as a result there is a tendency for important work to be ignored for years and worse still for the understanding of how the work mas actually done never to be brought out to help in the teaching of the subject. It is, therefore, of extreme importance that we improve scientific education by helping the teachers not only a t the college but also a t the high school level to impart the excitement of chemistry and science in general so that the value of science, and chemistry in particular, can be transmitted to their precious young charges. To be absolutely honest and practical we must try to interest the young student in science, and chemistry in particular, by showing him'the excitement and wonderful thrill of discovery itself. We must show him how absolutely enthralled the top chemists have been during their active lives, and how productivity has accompanied this devotion to the science for its own sake and not just for its usefulness to mankind. For as useful as science is to society, this is not the reason scientists join up. I t is the reason society supports them and their effort, but it is not the reason they take up the challenge. There is no substitute for the burning curiosity about nature which only scientific research can assuage for young scientists. The teacher must remember this always. Only inspirational teaching can suffice.