Editorial. What is Analysis? - American Chemical Society

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, Editor

What Is Analysis? What Is the Role of the Analyst? THE Division

of Analytical and M i c r o Chemistry of the AMERICAN CHEMICAL w i l l sponsor a symposium on the training of analytical chemists at the spring meeting in Chicago. Teachers, employers, and practicing analysts will present their v i e w s and a number of w o r t h - w h i l e suggestions undoubtedly w i l l result from these discussions. The action of the Division o f Analytical and M i c r o Chemistry i n p r o v i d i n g a forum for a discussion of the problems connected w i t h the future training of analytical chemists is timely and i n o u r o p i n i o n the symposium w i l l attract w i d e attention from analysts and others w h o are concerned w i t h the field of analytical chemistry. The editors o f ANALYTICAL CHEMISTRY are very much interested i n the p r o b a b l e future revision and expansion of courses i n analytical chemistry. As a preliminary step w e believe i t ddvisabie to obtain expressions of o p i n i o n from teachers, industrialists, plant executives, and practicing analysts i n b o t h government and private (1) W h a t i s analysis? and (2) W h a t is the r o l e of the industry o n the questions: analyst? In other words, w e should l i k e to present definitions of dnalysis and d e scriptions o f the r o l e of the analytical chemist a s v i e w e d b y vdrious segments of the chemical field. W e present b e l o w the comments oft w o practicing analysts employed b y private industry, a representative o f management, a professor of chemistry, and an analyst in government service. O t h e r v i e w s w i l l b e published in future issues.

SOCIETY

Wayne W. Hilty, Eli LiIIy and Conrpany

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SALPTICAL chemistry,

from the practicing analyst's point of view, is determining the composition of a given compound or group of compounds, as to quality or quantity or both. It involves the application of proved chemical reactions ' and physical properties, the development and the adaptation of new methods for specific evaluations. The analytical chemist is often asked t o predict ryhat will take place when certain compounds are mixed 01 combined. S o t infrequently he is assigned the task of determining what actually has happened to a product that has deteriorated or changed in either some chemical or physical manner. The vaiious types of techniques thah are involved in chemical analysis as it is applied today embrace not only all fields of the science of Chemistry but also a considerable amount of physics and mathematics. As a necessary prerequisite, a good analyst must have a broad working knowledge of these basic sciences. He should also have the intellectual ability and the manipulative skill t o take practical advantage of the various appi oaches to the analytical methods that are already aoailable. Furthermore. it is essential that he be endowed with the creative ability that will enable him to propose and to develop new methods and new tools as new analytical problems are encountered. The rapid progress and advancement made in the field of chemistry and related sciences in the past two or three decades make it necessary for the analyst t o turn to methods 821

other than the isolation and determination ~ r specific f elements or groups of elements n-hen attempting to analyze a given compound or mixture. The advent of physical and physical chemical procedures makes it imperative that he knox something about, and how best to utilize, the various phenomena of these new techniques. His knowledge of spectroscopy. for inst'ance, must be basic and thorough. He must be competent in applying the identification and assay techniques of the organic chemist, the biochemist, and those of all other branches of chemistry; and certainly not the least important among t'lie requirements for a good analyst is his ability to compose a complete and intelligent report of his investigations. Anyone who is striving to keep abreast of the rapid progress that is now being made in the advancement of the various fields of science must realize that it is becoming increasingly imperative that graduates be adequately trained and prepared to embark upon the challenging career of an analytical chemist,. The time has arrived when it is highly desirable to give more consideration to the basic requirements in the selection and in the training of those who are t o be responsible for t,he future of analytical chemistry. Unless a firm and intelligent foundation is laid, t'he careers of our future analytical chemists n-ill be seriously impaired. In order to prepare a chemistry student properly and adcquat'ely for such a career, it is urged that the curricula of our institutions of learning require strong fundamental and applied courses embracing chemistry, physics, mathematics, instrumentation, related sciences, rhetoric, and composition.

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V O L U M E 19, NO. 1 1

A keen personal interest in the analytical approach to chemical problems is also of outstanding value to the prospective analytical chemist. Such an attitude will go far in providing the personal satisfaction and the ingenuity that contribute so much to the development of a successful analytical chemist.

John F. Flagg, G e n e r a l Electric Company

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is chemical analysis? In a general fashion the purposes and aims of chemical analysis are clear, and the utilitarian aspects of the subject have long been recognized and stressed. This has been a t once a source of strength and of weakness, for the connotation of applied science implied a false state of completeness even though adequate development may have existed. The full extent to which chemical analysis has grown in recent years, the fields it now encompasses, and the demands its successful practice exacts are such as to alter this picture considerably. From humble beginnings chemical analysis has become an increasingly exact science. Developing the basic laws of chemical combination, determining atomic weights, and accumulating so much information regarding the composition of our physical surroundings early in the nineteenth century are notable contributions of chemical analysis in its first stages of development. Since then constantly increasing demands have been made on the science. These hare taken many forms: for greater accuracy; for analyses of complicated, manycomponent systems; for determinations over concentration ranges once thought impossibly wide; for speed; for mechanization and automatic control; for procedural development, brought to higher degrees of reliability. To meet these demands much accessory equipment has been called in. Optics, electronics, and many other branches of science once considered outside the domain of chemistry now contribute to chemical analysis in an everyday fashion. Thus has much of chemical analysis come to consist simply of making physical measurements. For all the science there is yet much art in chemical analysis, for in countless instances the quality of the experiment is in no small degree a measure of the skill of the experimenter. -4 polished technique and a seasoned chemical judgment are no less the ingredients of a chemical analysis than the apparatus employed, or the basic theory upon which the process is built. The field of microchemical anaIysis with its many specializations well illustrates this. Thus modern chemical analysis is a composite of art and science, of theory and application, of prejudice and detachment, directed toward the performance and interpretation of physical and chemical measurements on systems to evaluate their composition. What now is expected of the analyst, through whom all this becomes possible? First, he must be thoroughly trained in all aspects of chemistry, with emphasis placed on general principles rather than premature specialization, and well grounded in the fundamentals of mathematics and physics. The intelligent understanding of methods and apparatus, the ability properly to appraise results, and a store of information upon which to draw when meeting new situations are all part of the equipment the analyst can reasonably be expected to possess. But beyond this the analyst must be skillful; the lack of this may be more prejudicial than lack of knowledge, though scarcely can one in the true sense be unaccompanied by the HAT

other. Lastly, and ranking in importance with the other qualities, the analyst must be versatile. He must be in succession researcher, gadgeteer, mechanic, trouble shooter, adviser, organizer; prepared to expect the unexpected and equipped to perform the impossible without hesitation. But, then, is the lot of the analyst after all so different from that of any other scientific worker? To a great degree, probably not. Yet the responsibilities of the analyst resemble somewhat those of the physician in so far as much that is important may depend directly upon the work of his hands and the judgments he makes. In the light of this the standards, though high, are not unreasonable.

B. L. Clarke, M e r c k & Co., Inc.

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analysis is, of course, the breaking down of complex substances into simpler substances. It is the opposite of chemical synthesis. These two types of operation constitute what the chemist does both in the laboratorv and in the plant. If he does analysis (in this etymological sense) in the manufacturing plant, he does it because the substance he wishes to produce is simpler than his raw material (gasoline from petroleum). In that case, however, the chemist is not customarily called an analyst. That term is reserved for the laboratory chemist whose purpose is not to produce something new from hie starting material, but rather to discover the constitution of his sample. He often carries out exactly the same operation as does his factory counterpart; but with the two essential differences that he works on a smaller scale and throws hie products down the drain once he has observed and measured their color, odor, refractive index, etc. Thus, the analytical chemist is one who breaks substances down in order to find out of what they are made. Two points deserve emphasis. Because the analytical chemist is really a manufacturing chemist who works on a reduced scale, his basic training in the understanding of chemical reaction cannot be very different from that of the factory chemist (only when it comes to technique must their trainings diverge). Thus the analytical chemist is first and foremost a chemist. Although he is a specialist, he is nonetheless a fullfledged member of the chemical profession, doing work as important as that of his professional colleagues in other branches, and deserving of comparable emoluments and prestige. The other point is that modern analysis frequently avoids the actual physical destruction of the sample, by the use of instruments, like the spectrophotometer, that in effect extend the senses and allow the analyst to observe molecular structure without the crudity of picking the molecule apart. Not only are these instrumental methods more elegant; they are potentially more efficient, and are more and more used in industry where efficiency counts. Obviously, then, the curricula for the training of analytical chemists must give great emphasis to analytical instruments and to the physical basis underlying their operation. Similarly, because modern statistical knowledge is nowadays a necessity for attacking the twin problems of design of sampling procedures and interpretation of analytical data, the student should be given some training in this field. Thus equipped, the graduate will have assured an important place in industry. HEMICAL

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N O V E M B E R 1947 Philip J. Elving, Pnrdae University

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or thirty years ago there was little difficulty in defining analytical chemistry. Analytical chemists were then fairly well restricted to the inorganic mineral type of analysis. The enormous advances that had been made in the analysis of organic materials, as in the Pregl techniques, were largely due to and in the hands of organic chemists. At the aame time, advances in analytical chemistry were being made a t a tremendous rate by the biochemists, but the analytical chemists in industry and in the universities had, unfortunately, but little part in it. Most research in analytical chemistry in our academic institutions was restricted to the fundamental techniques of gravimetric and titrimetric methods, although men like Burman, Kolthoff, hlellon, and Willard were beginning to expand the field of academic analytical research. It is less than a score of years since Nitchie’s noteworthy paper on quantitative emission spectrography prophetically began the first issue of the ANALYTICAL EDITION in January 1929. Today, it is difficult to define analytical chemistry precisely. As a first approximation, the subject may be limited to all techniques and methods for obtaining information regarding the composition, identity, purity, and constitution of samples of matter in terms of the kind, quantity, and groupings of atoms and molecules, as well as the determination of those physical properties and behavior which can be correlated with these objectives. Thus, analytical chemistry includes means of securing not only knowledge of the elemental composition, qualitative and quantitative, of materials but also a knowledge of the way the atoms are put together to form the molecular units as in the determination of organic functional groupings, While analytical chemistry does not include the use of x-ray diffraction in deteimining the unit cell of quartz, it does include the use of x-ray diffraction to determine the presence and amount of quartz in a sample of a dust or in a rock specimen. Analysis may then be considered to be the application of analytical chemistry to obtaining qualitative and quantitative information about the nature of matter at the individual limit of the atomic level or higher. Analytical chemists are those principally concerned with the design, planning, and systematizing of the field of analytical chemistry. As has often been emphasized, they must have, if not a working knowledge, a t least an awareness of the applicability and limitations of methods, techniques, facts, and instruments from accumulators (electrical variety) to zinc (analytical chenlistry). I n solving analytical problems, they must bring to bear on the situation many streams of knowledge; in devising analytical techniques, they must be alert to the possible development of any device or means of measuring chemical reactivity or physical behavior into a means of determining composition. In approaching an analytical problem, the analytical chemist must have the background and ability to evaluate possible analytical methods from the viewpoints of interference, range of applicability, necessary modifications, and preliminary treatment, as well as the valid interpretation of the experimental measurements obtained. He must know not only how to use the multitudinous analytical techniques a t his disposal, but, perhaps more importantly, when to use them. The analyst might be defined as the one who puts into practice the work of the analytical chemist, as the person WENTY

823 concerned chiefly with the exercise of analytical chemistry. In many situations, the analytical chemist and the analyst are identical; each must always be something of the other. Both the analytical research chemist and his co-worker, the practicing analyst, have the same goal-knowledge of the composition and constitution of matter a t the limits specified. C. 0. Willits, Eastern Regional Research Laboratory

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HE analytical chemist today plays a more important part in an agricultural chemical research program than ever before. The rapid expansion of the chemical industry, with the accompanying development of a wide variety of new materials from agricultural sources, has made demands upon the analyst far greater than those of a few years ago. He is now expected to contribute much toward the evaluation of products and processes developed, regardless of their complexity. The analytical problems, in general, deal with applied organic analysis for the establishment of the presence or purit). of organic compounds and for the determination of material balances in new chemical processes. In the solution of these problems the analyst is required, through the use of either micro or macrotechniques, to determine by elemental 01 group analysis the purity of organic compounds and the composition of mixtures separated or synthesized from agricultural materials; to identify and measure the amounts of naturally occurring organic and inorganic constituents, such as starch, glycerides, sugars, tannins, pectin, rubber, protein, ancl ash, regardless of whether they occur in large or tiace amounts; t o be competent in the use of the special, as well as of the O I dinary, instruments required in the analysis; and when ne(*essary t o develop new or modified analytical procedures. Unfortunately, most college graduates are unable to qualify as analysts capable of performing even a portion of these duties. Instead, they must be trained on the job, m-ith a consequent interruption of the research program. The prevailing misconception that all college-trained chemists are trained analysts must be corrected, with an accompanying change in the curricula of many of our colleges. The on-the-job training period could be largely avoided if the student analyst were to be given a coordinated analytical course which would include, in addition to the fundamental courses noK offered, training in organic qualitative and quantitative analysis, applied organic analysis, including the principles for the estimation of constituents of agricultural and food products, and instruction in the use and application of analytical instruments now often available only to advanced organic, and physical chemistry students. Sufficient training in physics must be given to enable the student to understand the principles and operation of the instruments used. Such a course will develop analysts with a broad general background who can quickly adapt themselves to the laboratory’s problems. It will also keep the instruction of analytical chemistry progressive and based on current problems. Improved curricula, with a clarification of the requirements and duties of a modern chemical analyst, will do much to relieve the shortage of able analysts, since it will attract more and superior students to the field. The profession of analyJica1 chemistry in industrial agricultural research has grown UR by demand, and the profession must now demand that the colleges provide analytical chemists.