NOVEMBER, 1948
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BEGINNING COURSE IN QUANTITATIVE ANALYSIS I. M. KOLTHOFF University of Minnesota, Minneapolis, Minnesota
Q u m T m m I m analysis, as all other fields of chemis- sity of Minnesota and myself this would be highly untry, is not static but dynamic. New discoveries in desirable, especially for the students in chemistry and chemistry and physics extend and broaden the scope of chemical engineering. The aims and objectives of a beginning course in analytical chemistry. Although the fundamentals of gravimetric and volumetric analysis remain essential quantitative analysis for chemists and chemical enparts of quantitative analysis it is timely to consider gineers, designated below for the sake of convenience whether the presentation of new principles and modern as chemists, are quite different from those of a begindevelopments should not be included in a beginning ning course for premedical students, home economics majors, and other groups whose major interest is outcourse. We should approach the entire problem in a qpirit of side of chemistry. As chemists we are mainly concerned conciliation and compromise. As in all daily problems with and interested in satisfying the needs of the stuin life we should be willing to compromise on extreme dents in chemistry and chemical engineering. Other views, and if possible do justice to all reasonable views. departments which request service courses in quantitaIf time were not a factor we could teach all the theo- tive analysis should state their own aims and objectives retical and practical aspects of quantitative analysis. and the department of analytical chemistry can try to This may be desirable for all graduates majoring in accommodate these groups. The aims and objectives analytical chemistry but we are concerned here with the of a "service" course in beginning quantitative analysis fundamental introductory course. First of all we have are so different from those for chemists that a t Minneto reach an agreement with our colleagues in the other sota we give a differentcourse for the chemists than for major fields in chemistry as to how much time should the outsiders in chemistry. Let us first consider the be devoted to a fundamental course in quantitative contents of a fundamental course for the chemists. Stated briefly, quantitative analysis deals with the analysis, and then we have to compromise among ourselves as to what such a course should offer. No ele- determination of the composition of one compound or mentary course aims a t educating experts in a given any mixture of compounds. Quantitative analysis is an field. Whatever the aims and objectives of an elemen- art and a science. When a student has acquired the tary course in quantitative analysis are we should elementary principles of the art of analytical chemistry agree from the outset that a student who has passed he has the necessary background for carrying out such a course successfully is not an expert in quantita- analyses by given procedures but he is not an analytical tive analysis; a t most he has acquired the background chemist. Teaching the "doing" of an analysis is only part, alto become an expert. The question has been asked: "Fundamentally, though an essential one, of a fundamental course in what should the beginning course in quantitative analy- quantitative analysis. But let us balance this with an sis include in order best to train for future technical understanding of the science of quantitative analysis, work such groups of students as chemical engineers, lest the student, after finishing his course, might feel home economics majors of diverse interests, premedical like the man described in the opening paragraphs of the students, and ~rosuectiveresearch chemists?" This Preface of a book written bv Newth.' written in 1898:
JOURNAL OF CHEMICAL EDUCATION "A man once brought his son to the Royal School of Minesnow the Royal College of Science-with the request that he might be taught to 'do copper.' He did not. want his boy to 'waste his time learning about oxygen and hydrogen, and all that,' hut he wished him simply to learn to 'do oopper.' "Although seldom expressed with such refreshing candour, the desire to do analysis without learning more.t.han the minimum amount of chemist,ryis still very prevalent; and, unfortunstrly, chemical analysis i~ a subjcct which may be, and frequently in, taught and practised in such a, manner as to degrade it to the, levcl of a purely mt:ohanical and often quite unintrlligihle serit.s of mle-of-t,humb operations."
Quite generally, the aims of the undergraduate education for chemists are to provide the students with a balanced background in the fundamentals of the various fields of chemistry, without trying to educate specialists in any given field. The classification of chemistry into various fields has definite advantages, but the major subjects are closely interrelated and it is hardly possible to become an expert in any of these fields without a thorough background in the other major subjects. In quantitative analysis we make use of the facts and theories of other major fields of chemistry and vice-versa; progress in these other fields requires a knowledge of and experimental acqnaintance with quantitative analysis. Based on these views a chemistry student should be equipped in his fundamental course in quantitative analysis with the knowledge and the skill to interpret and carry out analytical procedures and with the uuderstanding of the possibilities and the scope of quantitative analysis. In such a course it becomes evident that the scientific advancement of analytical chemistry is not possible without making use of the facts and theories provided by physical, inorganic, and organic chemistry and physics. In his course in general chemistry the student has been presented with enough elementary physical and even organic chemistry to understand the significance of these subjects in elementary quantitative analysis. For a proper appreciation of the role of quantitative analysis in the various fields of chemistry the student should also learn of the contributions made by quantitative analysis in the development of these various fields and of the possible role of quantitative analysis in the further development of these subjects and in chemical research in general. The successful approach of a new "pure" or "applied" research problem often demands first of all the development of suitable analytical methods. I t is not necessary to go far back in history to find a great number of suitable and impressive illustrations of this thesis. In my own recent experience I could refer to the role of quantitative analysis in the development of our understanding of emulsion polymerization. A rational study of the kinetics and mechanism of this type of polymerization became possible only after suitable analytical methods had been developed. I t maybe argued that the great majority of students lack the originality, ability, and initiative to make creative use of quantitative analysis in their later prc-
fessions and that education in quantitative analysis on such a broad basis, therefore, would not be justified. However, such an argument would hold equally tme in the other fields of chemistry and, if accepted, would lead to a lowering of the standards in the entire education in chemistry. I believe that only very feu, people would agree with such a view, if it nere only for the fact that it would lead to a serious reduction of the background of the small group of outstanding students who are destined to become leaders in their chosen fields. Summarizing, the major objectives of an elementary course in quantitative analysis are to provide a balanced education in the theoretical and practical fundamentals of gravimetric and volumetric analysis, and to imbue the student vitb the proper appreciation of the scope of quantitative analysis, its relation to the other major fields of chemistry, its significance in the scientific development of these fields, and its role in "pure" and applied research. In this way justice is done to the position of quantitative analysis among the other major fields of chemistry. The student having passed such a course is still a novice and not an expert in the field of quantitative analysis. The classical fundamentals of gravimetric and volumetric analysis remain the essentials of the elementary course. In order to cultivate a proper appreciation of the scope of quantitative analysis it is highly desirable in such a course to make the students acquainted with the elementary principles of more advanced subjects, like electrometric methods, optical methods of analysis, difficultiesinvolved in the analysis of complex materials for major and minor constituents, analysis of microquantities, instrumental methods of analysis, etc. The student who is interested in broadening and deepening his background in quantitative analysis will have an opportunity later to take advanced courses in the field. Based on these general views the following topics are discussed in the fundamental courses (2 quarters, 5 credits each) in quantitative analysis for chemists and chemical engineers in the University of Minnesota: accuracy and precision, errors and sources of errors, analytical balance, solubility, and dissociation equilibria including oxidation-reduction reactions, properties of precipitates, coprecipitation, hygroscopicity, methods of separation, use of organic reagents, electroanalysis, calibration of weights and volumetric glassware, understanding and interpretation of properties of indicators in volumetric analysis, general use of the various volumetric reagents, oxidizing and reducing agents, elementary principles of optical methods of analysis. Ample time is reserved for a discussion of stoichiometry and more general problems in recitation perioas. For the entire course 35 lectures and 20 recitations are scheduled. For the laboratory work 180 hours are scheduled. The following determinations are made: Grauimetric: Water in barium chloride, iron as oxide, chloride, sulfate, calcium and magnesium in limestone, silica in a rook, phosphate in apatite rock, electrolytic copper.
