SELECTING RESEARCH PROBLEMS FOR STUDENTS1 E. EMMET REID Johns Hopkins University, Baltimore, Maryland
The writer i s Professor Emeritus of Johns Hopkins University and for ten years has been visiting about a dozen Southern institutions in the interest of research. Research worthy of publication in standard journals can be done by M.S. and even by B.S. candidates. The student must get so interested in his problem that he will give all he has to it and his teacher must be research-minded.
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FIRST let it be said that 'the student should do the selecting. The vital spark in research is the feeling that one is on one's own. However, in this finite world, there are limitations to free will: The acceptance of the status of student implies the recognition of the need of some guidance. In a cafeteria one is limited by the varieties of food displayed, by the size of one's purse, and by one's appetite. The choice is influenced by the attractiveness 13-ith which the wares are displayed and by the prices. The professor should put before the student a liberal assortment of problems. Each should be made attractive by a statement of the end to be accomplished and its importance. Each should have a price tag in the way of an honest estimate of the difficulties involved. Selling the problem to the student is of critical importance. What he does with it will he determined largely by how it stirs his imagination. If his interest becomes intense enough he will dream about it and be alert enough tocatch the unexpected. - Students who are likely to undertake research problems are usually those who are looking forward to chemistry as a career. Whether they go into industry a t the B.S. level, or after further study, or whether they are aiming a t plant operation or industrial research, they will do well to get first hand information about research, its methods, its joys, and its sorrows. Carload lots of commodities are sold on the basis of samples, why not sell research'in the same way? The samples may be small but they must he representative; they must not be phony or make-believe. Research is finding out something not previously known. Hence the problems suggested must pertain to the un known. Normally there are three parts to research: a literature search, making the experiments, and reporting the results. The student's sample should contain all three
' Presented before the Division of Chemical Education a t the 113th Meeting of the Arnericsn Chemical Society, Chicago, April 19-23,1948.
of these. This looks like a large drder hut i t is presumed that the student has already had instruction in the use of chemical literature, in organic preparations, and in English composition. Having been led through these courses he may take a few steps on his own. Naturally he cannot be expected to cover much ground, but emphasis should be put on quality and thoroughness in what he does do. The addition to human knowledge may be small hut it must he real. This depends on its quality, not on its size. A speck of gold in the miner's Dan is as really gold as the largest nugget from the ~ l o n d i k e . In fact, much of the hoard ofgold a t Fort Knox has been assembled from tiny bits, many of them microscopic. Any real addition to knowledge is worthy of publication. Information becomes of value only when it is made available to those who may need it. The matter of pnblication is of prime importance. It is to be considered a t the start in proposing a problem and should be kept before the student continuously in order that the quality of his work may be maintained and that all the desired data may be secured. At the finish loose ends must be gathered up and the results written up in suitable form before the task is considered complete. In choosing a problem the matter of size is critical. In the cafeteria the slices of mince pie are so small that there is little danger of indigestion, but as chemical problems are being handed out free, why not take a large one? One ambitious B.S. candidate undertook the study of the "drying" of linseed oil. The severest limitation in research is the matter of time. This is true even in the largest organization. It is acute with the candidate for a bachelor's degree who has only two or three afternoons a week for research. The aspirant for the master's degree has more time but still not enough for a large task. This means that the problems must be screened to size and done up in small packages. Larger problems must be broken up into pieces. The student should be discouraged from taking a task that he has not a reasonable expectation of completing. After selecting a problem the student should make a literature search. If, for instance, it is the preparation of a series of esters of sorbic acid, he should list all the known esters of sorbic acid and note how they have been made, going to the original literature as far as possible. He should read up on esters of similar acids on which more work has been done. Then he should write an outline of what he proposes to do. All of this should be submitted to his professor for criticism and advice as to what experimental work should be undertaken.
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The preparation of organic compounds is recommended as the most suitable field for the beginner in research. Organic chemistry is the crowning achieve ment of the human mind. In no other realm have so many tens of thousands of facts been so logically arranged and fitted together into such a magnificent stmcture. By 1910, according to Richter, 144,150 organic compounds had been prepared; by now the number has probably reached half a million. Each of these fits into its niche in the system and its properties are related to those of adjacent compounds. Each is a member of several series, thus hexyl butyrate is between amyl and heptyl butyrates in one series and between hexyl propionate and valerate in another. The properties of these five esters are related among themselves and to those of the other members of the two series. These series rnn parallel to other series. It is like putting together the pieces of a jig-saw puzzle but it is farmorefascinating, since a picture is being created which no mortal eye has ever seen. In fillmg in gaps in a series the data for the new compounds should he plotted along with those for the old. This characterizes the series and, incidently, shows up errors. The whole series gains interest by being taken as a unit. There is satisfaction when the new compounds fall into their proper places and have the expected properties. There is a thrill when this is not the case. Finding out the reason for the discrepancy may lead to a discovery. The more accurate the determinations the greater is the probability of turning up someth'mg interesting. The discovery of the planet Neptune was due to the observation of minute differencesbetween actual and calculated positions of Uranus. The data on the lower paraffins are sufficiently comprehensive that the boiling point, density, and refractive index of any one of the 334 unknown dodecanes can be predicted with accuracy. In other series our information is so fragmentary that we can go only a little way with such predictions. To extend our knowledge of the relationships of the properties of compounds of one series among themselves and to those of the members of other series many additional thousands of compounds will have to he made and their properties determined with accuracy. Unfortunately the data on a large proportion of the compounds already in the literature are so poor that they are of little use for comparisons. Remaking imperfectly !mown compounds, purifying them and determining their properties is a real service. Filling in blanks and supplying accurate data for chemical literature are tasks particularly suited for student research. Candidates for the doctor's degree must have bigger problems and industrial chemists are under pressure to concentrate on items which appear to have commercial value. Skill in the preparation of organic compounds is a prime requisite in many fields of industrial research. In the quest for new and better medicinals many thousands of organic compounds have been prepared. Certain derivatives of barbituric acid were found to have valuable soporific properties; hundreds of others have
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been made having all sorts of groups in all possible positions. Sulfanilamide was found to be potent; over a thousand of its derivatives and analogs have been made and tested. Some 14,000 compounds have been synthesized and tried out as antimalarials. Antiseptics, local anesthetics, and other classes of medicinals have received much attention. Dyes, plastics, protective coatings, synthetic rubber, Nylon, and the like are products of industrial research in all of which the preparation of hosts of organic com~ o u n d was s fundamental. In organic synthesis there are available problems of all degrees of difficulty from the simplest, which are scarcely harder than those in a course in organic preparations, to those that have baffled some of the best chemists for decades. The synthesis of new acids, esters, amides, and the like is a natural follow-up of the usual course in organic preparations. Yet i t requires considerably more than simply following directions. Lahoratory manuals are so well written that a student can turn out good results with little understanding of the reactions involved, but the preparation of a new compound, even a homolog of one given in the manual, requires thought. The proportions have to be recalculated and account has to be taken of different soluhilities, volatilities, and reactivities. When work is being done for publication far more attention has to he given to purity of starting materials and to the accuracy of the determinations made. Another reason for choosing organic syntheses as a field for student research is the wide variety and great number of compounds which can be made by estahlished methods from materials that are now a t hand. Fifty years ago organic chemicals had to be imported. Each spring the requirements for the coming year's research were figured out and an order sent off to Kahlbaum in Germany for fall delivery. This restricted research to predetermined lines. One worked on chemicals that were in stock. There was little use in dreaming up new problems. Ethanol was the only common alcohol. Methanol, propanol, I-butanol and i-amyl alcohol were the only others available. I-Propyl bromide had to be made by isomerizing the normal bromide with aluminum bromide. T-Butyl alcohol was obtained from acetone and methyl iodide by the Grignard reaction. Now things are very different. Eastman lists about 3,000 organic compounds of research grade. From five alcohols and five acids twenty-five esters can be made; from 50 alcohols and 100 acids the number of possible esters is 5,000. A study of the fourth edition of Beilstein which brings chemistry up to 1910 shows that ethyl esters have been made from practically all acids methyl, propyl, i-butyl and i-amyl, but that esters from n-butyl, n-amyl, and higher alcohols are scarce. Acetates of alcohols are common, formates and propionates less so, while n-valerates, caproates, and the like are usually wanting. Since 1910 the number of gaps that have been filled in is large but the number of those that (Continued on page 5$4)
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SELECTING RESEARCH PROBLEMS POR STUDENTS (Continuedfrom page 518 )
remain is many times greater. Of these 3,000 compounds hundreds have become available, only recently, which means that few of their possible derivatives have been prepared. The advertisements in Chemical and Engineering News and in other chemical publications are exciting , reading to the research-minded. Various corporations display lists of organic compounds which are now to be had, some in drum lots and some in tank cars. Charts are published giving typical reactions and the reader is invited to write for bulletins giving more information. Some of these compounds have been sold previously a t from 10 to 30 cents a gram and some were not even listed. This means that comparatively little work has been done on them and that almost anything that can
be made from them will be new. The corporations that are promoting these compounds are usually liberal in furnish'mg information and, sometimes, free samples to educational institutions. It is to their interest to have research on them published. Almost any one of these advertisements can suggest attractive problems for 10 to 50 students. Many institutionsgive courses in qualitative organic analysis in which alcohols, acids, aldehydes, ketones, and other classes of compounds are identified by crystalline derivatives. Among the compounds now on the market there are many for which suitable crystalline derivatives is a worthwhile research problem which may be an extension of the regular course. There is always the search for better identifying reagents.
