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THE MOTIVATION OF STUDENTS IN THE TEACHING OF QUANTITATIVE ANALYSIS C. C. MELOCHE University of Michigan, Ann Arbor, Michigan
E V E R Y teacher knows that in his own work and in the work of his students intense interest contributes greatly to high efficiency. Enthusiasm for the job is a close relative of determination and aids materially in the h a 1 accomplishment. For the present purpose motivation may be defined as any means which are ethically utilized to provide the right incentive for the student to make the best possible use of his time. Training in quantitative analysis is usually required for students of chemistry, chemical engineering, metallurgy, pharmacy, and agriculture, recommended or required for premedical students, students of home economics, and some others. In a heterogeneous group of this sort, one occasionally encounters the student who is interested in nothing more than the satisfaction of the minimum requirement, who sincerely believes perhaps that the study of quantitative analysis is not germane to his later success. Even such a student can be persuaded that "whatever is worth doing a t all is worth doing well" and so be led to pursue the course more vigorously as long as it is required in his case. Proper motivation, however, can and often does accomplish a seemingly impossible change of attitude and lead to a gratifying final result. The question whether all chemists should elect quantitative analysis need scarcely be debated. Due to premature interest in narrow specialization even the chemistry major may fail to realize that the final solution of many of his future problems lies in the proper integration of information from cognate fields. How greatly would the analytical chemist he handicapped without the primary standards, delicate indicators, and selective reagents supplied by his colleagues in organic chemistry! At times, indeed, he is forced to borrow a technique developed originally in this same field. On the other hand, the organic research chemist at the end of a brilliant synthesis compares the theoretical composition with the actual ultimate analysis. Mixed products of the organic chemical industry often present intricate analytical problems which the analytical chemist is specially qualified to solve. The analytical chemist and the physical chemist are likwise mutually indebted. Even in his so-called purely chemical methods the analytical chemist applies a physioochemical principle a t every turn. Many of the properties measured and studied by the physical chemist are functions of the concentration and so are often utilized by the analytical chemist in the measurement of concentration and the determination of the total amount of the constituent. Physical and physico-
chemical instruments are utilized by the analytical chemist in great variety. On the other hand, the physical chemist often follows the course of a chemical reaction by a purely analytical method. In the study of chemical equilibria, the phase rule, and the speed of chemical reactions, quantitative analytical methods must often be skillfully applied. While the colloid chemist has contributed much to analytical chemistry he in turn secures valuable information in regard to surface reactions by refined methods of analysis. Likewise, the electrochemist who has contributed many excellent analytical methods uses still other analytical methods in his determination of normal electrode potentials, transport numbers, e t ~ . The atomic physicist often requires the help of the analytical, chemist but in turn furnishes the analytical chemist with valuable radioactive isotopes. The biochemist contributes as well as uses analytical methods while the geologist and the mineralogist would be among the first to acknowledge important applications of analytical chemistry in their fields. Enough has been said to show that chemists in their various fields are dependent upon each other and upon other scientists to a large extent and that no advantage is gained by strict compartmentation of science. The undergraduate chemist must eventually realize this fact and so'not treat his analytical chemistry as a subject altogether apart from the rest of chemistry and of science. Fortunately the interdependence of the various fields of chemistry becomes evident a t an early stage in the chemist's experience. He soon observes also that some of the most important modern research is conducted by individuals whose training is broad enough to bridge the gaps between separate fields of science. A similar view has been expressed by Kolthoff (7). The young chemical engineer is sometimes led to believe that he willnever be expected to carry out chemical analyses personally, that all the analyses which he will ever require will be done by others. He is doubtless unaware of the fact that the type of hard-boiled executive who prefers to test the skill of the young engineer in the laboratory, possible even in the analytical laboratory, is still alive and active. Moreover, in a small organization the young chemical engineer may find it distinctly advantageous to prove on occasion that the plant can he kept running because he is a good analytical trouble shooter. The chemical engineer, like the chemist, discovers as he progresses that the answers to many of his research problems are obtained
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in terms of thoroughgoing quantitative chemical analyses. In fact, a well-trained chemical engineer is often himself the author of an excellent method of analysis. It may be sufficient to observe that the methods of quantitative analysis are directly or indirectly involved in the evaluation of the great majority of raw materials and hished products of modern industrial operations and even the young engineer is well aware of the fact that the success or failure of a chemical manufacturing enterprise may easily depend upon relatively small differencesin the quality and composition of raw materials or finished products, differences easily discernible by the young engineer with moderate training in analytical chemistry. The amateur chemical engineer can well afford to contemplate that the study of quantitative analysis is probably one of his best opportunities to study the conditions under which reactions go sensibly to completidn, conditions which will doubtless eventually affect his yields and therefore his profits. Training in analytical chemistry enables the chemical engineer to interpret more critically the chemical analyses necessarily carried out in connection with many chemical engineering processes. Such training may also help him to take a more dependable vien- of many other important matters in his line of duty. The value of training in quantitative analysis to the chemical engineer has been well explained by Knight (6). The metallurgist is in much the same position as the chemical engineer. The products of his industries are valuable and the specifications as to composition often rigid. A careful chemical analysis must frequently decide an important question. The young metallurgist will therefore appreciate the advantage of being able to carry out or supervise his own analytical work. The problems of metallurgical analysis are among the most intriguing as he will soon discover. Metallographic studies which seek to explain the various physical properties of alloys by the formation of intermetallic compounds, solid solutions, and eutectic mixtures, frequently involve a quantitative knowledge of the composition preferably obtained by chemical analysis of the alloy. The young pharmacist is sometimes asked to ponder the embarrassment of the drug manufacturer or dispenser who discovers too late that a preparation intended to cure disease or alleviate suffering actually poisoned the patient. When chemicals and mixtures of chemicals are being prescribed and dispensed for internal human consumption what can be more appropriate than a knowledge of their composition and purity and how better can this information be secured than by a good chemical analysis? Only the pharmacist with an adequate background in analytical chemistry can understand the requirements of drug analysis or take full advantage of the detailed information contained in the Pharmacopoeia and the National Formulary. When the pharmaceutical chemist is asked to serve as a medical technologist or to act as a toxicologist or to aid in the enforcement of the pure food and drug act
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his knowledge of analytical chemistry will often be his chief reliance. The value of analytical chemistry to the pharmacist is plainly stated by Jannke (4) while the debt of the chemist to the pharmacist is suitably acknowledged by Elving (8). The wise young pharmacist, therefore, knows that he can well afford to take his training in quantitative analysis seriously. The student of agriculture soon realizes that modern advance in agricultural science has closely followed the application of chemical analysis to agricultural problems. After the main constituents of plants and plant ash had been determined the essential constituents of good soil and of fertilizers became more evident. The analysis of soils is now considered sufficiently important so that in most areas all that the agriculturist need do is to submit a sample to the proper agency in order t o secure valuable information. The thrifty farmer buys his fertilizer on the basis of chemical analysis. Recently plant ash has been scrutinized for essential minor or trace constituents so that fertilizers can be manufactured according to more accurate specifications. When the chemical requirements of good stock and cattle feed became known it was a logical step to the sale of feed of guaranteed composition on the basis of chemical analysis. An inspection of the files of the Journal of the Association of Oflcial Agricultural Chemists reveals the prominent part which the analytical chemist has played in the field of agricultural chemistry. The role of the analytical chemist in agricultural work is also explained by Halvorson (3). The value of quantitative analysis to the student of home economics is made evident by Johnson (6). Interest in obtaining information and some training along the line of quantitative chemical analysis is therefore logical for the students of agriculture and of home economics. As previously intimated, quantitative analysis is not required for entrance by all medical schools. Neither is quantitative analysis absolutely necessary for success in the practice of medicine. However, the physician relies upon quantitative methods to some extent, the medical technician to a considerable extent, and the biological chemist usually regards quantitative analysis as a necessary part of his training while the medical research worker often dependsupouquantitativeanalytical methods in the solution of his problems. Important observations in this connection have been made by Bergeim (I). Once he has elected quantitative analysis the premedical student should acquire as much careful technique as possible and discover for himself the application of quantitative methods to his medical problems. The student who takes a course in quantitative analysis as part of a liberal education will acquire many interesting and valuable techniques. He will, on a t least a few occasions, it is hoped, experience the thrill of obtaining analytical results that agree closely or even precisely with the results obtained by experienced workers or required by theory. He will discover that a great variety of quantitative methods exist for the determination of the composition of an almost infinite
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number of materials, that these methods utilize and often beautifully illustrate a very large number of scientific principles. He should derive real mental stimulation from such a course and experience an improvement in his reasoning power and his power of analysis not entirely confined to things chemical. He will be better fitted for the pursuit of any of the several fields of scientific work previously mentioned and some others as well. If interested he will discover that by further advanced training including training in physicochemical or instrumental methods he can qualify for a posit,ion of analytical chemist, that this would often be a responsible position comparable with positions held by other scientific and technical experts. If the individual has sufficient training in analytical chemistry and cognate subjects he will be in a position to make definite contributions to his chosen field. The personal satisfaction in doing such work will far outweigh the financial reward but the renumeration will usually be commensurate with his training, ability, and effort. It is thus evident that many methods for motivating
JOURNAL OF CHEMICAL EDUCATION
a student of quantitative analysis are available. Probably the best method of all is the example of industry and accomplishment set by the teacher himself and the concern of the teacher for the student's welfare. Since, for the most part, only the more obvious methods of interest motivation related to a single subject have been discussed, it is true that any of the methods mentioned may prove ineffective in a given instance. However, in many cases the methods mentioned will prove to be helpful. If successful, the over-all result is an increase in the efficiency of the educational effort both for the instructor and for the student. Striving for real improvement in this direction is a part of the duty of every teacher of quantitative analysis. LITERATURE CITED
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~ ~ - , ~ - - - - - - --~ ,. i 2 j ELVING,P. J., J . Pharm. ~ d u c .7, , 21 (1943). (3) HALVORSON. H. A,, J. CHEM.EDUC.,15, 578 (1938). (4) JANNKE, P. J., J. Phmm. Educ., 5 , 28 (1941). (5) JOHNSON, M., J. CHEM.EDUC., 25,607 (1948). \
