AUGUST, 1941
INTEGRATING THE COLLEGE TOBIAS H. DUNKELBERGER Duquesne University, Pittsburgh, Pennsylvania
INTEE usual chemistry program .the student takes a succession of courses which are intended collectively to give him a fair comprehensionof the entire field of chemistry. If all of these courses were taught by the same person and if he had the specialist's ~ o m m a n dof each field, integration of all the information into a single, consistent picture would be practically automatic. Unfortunately, however, few, if any, such universalists exist; also, in the larger schools, the instruction of each individual student obviously must be accomplished by the joint efforts of a number of teachers, each a specialist in a restricted field. The all-too-frequent result is a lack of correlation among courses. The student receives little, if any, help in the coordination of his chemical knowledge and it is frequently not until he reaches the graduate level, if ever, that he acquires a perspective that enables him to view his various bits of chemical information as integral parts of a single unit field. Proper integration of courses implies, first of all, continuity from one course to another so that each course utilizes as a foundation the material of each preceding course and in turn furnishes the foundation for subsePresented before the Division of Cbemicd Education a t the 111th meeting of the Americm Chemied Society in Atlantic City, April 14-18.1947.
quent courses. One vay to encourage this would be to abandon the traditional names of chemistry courses and to teach only Chemistry I, 11, 111, and so on, using a logical, consistent development from each stage to the next. Administrative resistance and especially transfer troubles make this inexpedient, so we are forced to use the traditional course divisions. With this restriction, how can proper integration be secured? The problem, viewed realistically, is largely one of personnel. Every large department contains representatives of two groups: the traditionalists and the mddernists. Each group has its own approach to the subject matter of chemistry and in many respects the presentations are in conflict. A member of one group may, for example, teach the general course and a member of the other the analytical course. When this occurs not only is there failure to build on the foundation laid for the student, but, not infrequently and worse yet, the teacher of the second course either attempts to root out the previous foundation and replace it with his own or stubbornly proceeds to build on the foundation which he insists the student should have been given in the previous course. any effective progress can be made toward over-all integration, there most certainly must be inter-
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departmental accord. I t seems almost silly to suggest that all teachers of a science must agree on what they believe to be true about that science. But as long as scientific ideas change, as long as young men stop studying and grow old in ideas, this problem of interdepartmental disagreement will be with us. Teachers must themselves assume the responsibility of keeping abreast of new developments, of familiarizing themselves with the contents of the other courses with which their own course is supposed to coordmate. Course progress adds vectorially; therefore, if there is any deviation in direction the sum is not a maximum. It is disposing of the problem much too easily to say that department heads must become acquainted with the material actually being presented in the courses in their departments and must strive continually and mightily to see that all thesecourses proceed in the same direction. We cannot insist that all teachers agree on every detail of the subject, but they must agree on the important ideas that are to be presented to students, such ideas as, for example, the mechanism of ionization, acid-base theory, and molecular structure. But assuming an enthusiastic group of teachers in complete accord on questions of chemical fact and theory, how is the development from course to course to be carried out in order that each course may be built on, and make use of, the information from all preceding courses? What is the principle around which the entire program can be integrated? The most satisfactory integrating principle seems to be the structure of matter and the way in which structure determines properties. If we knew all there is to know about the structure of atoms and of aggregates of atoms we would know most of what there is to know about chemistry. Admittedly, troublesome difficulties harass us in the application of the principle to specific courses and subject matter. Serious deficiencies still exist-in our knowledge of the structural bases underlying common phenomena. Moreoter, the structural explanation of familiar phenomena is frequently difficult. How, for example, do we explain in a simple way why KCIOaand KN03behave differently when heated? Actually, however, these difficulties are long-range advantages; as gaps in our knowledge are filled in, the applicability becomes better and better. Also, greater familiarity with the material we now consider difficult will make it seem much easier; the graduate-course material of one generation is always showing up in the freshman courses of the next. The organization of the chemistry curriculum around the structure of matter must begin a t the beginning of the first course in chemistry, and this principle must be the guiding thought in this and in all subsequent courses. This requires drastic revision of the usual courses in both choice of subject matter and order of presentation. We have been working for some time on this revision in our courses a t Duquesne University. Some of the things we are doing can be described, but we still do not have the proof of the pudding-namely, students who have followed the program throughout.
JOURNAL OF CHEMICAL EDUCATION
The usual general chemistry course must be changed to one that could be subtitled Introduction to Physical Chemistry and Theoretical Physics. This is the critical course. Our development is not unlike that now coming into use in many universities: we start with the structure of the nucleus, of atoms, molecules, ions and go on from there. Much of the traditional descriptive material-properties of specific elements, specific compounds, industrial processes-must of necessity be ignored or, a t best, covered hastily, to give time for a more comprehensive presentation of the major concepts of chemistry, such as nuclear chemistry, the nature of chemical bonds, the kinetic basis of chemical reactions (collision theory, activation energy, the effect of size and shape of molecules, the statistical nature of reaction, etc.): The second course is analytical chemistry, starting with quantitative and ending with qualitative. This reversal of the traditional order may not be justified on a strictly logical basis, but it proves itself pedagogically. The reasons for and the advantages of this arrangement. are as follows. The fundamental chemical law is the Law of Definite Proportions. All freshmen understand this law and can carry out the simple stoichiometric calculations based on it. In principle gravimetric analysis is easy to understand and, while theprecise technique is somelvhat, demanding, the reasons for the precautions are usually obvious. In short, t h e background of information needed to begin reasonably intelligent laboratory work is already a t hand. While the student is going through representative gravimetric determinations in the laboratory the lecturer has a s . oj5portuaity to discuss stoichiometry,'to develop equilibrium calculations, to present information about solubility and the nature and properties of precipitates. The same easy theoretical approach is not possible for qualitative analysis nor for vo!nmetric analysis. In these fields the very first day's laboratory work presupposes knowledge of descriptive chemistry and equilibrium relationships which cannot be covered adequately in less than a few weeks. If this background information is not available the laboratory work is more of the much deplored cookbook routine. The information presented concurrently with the gravimetric laboratory work, however, leads logically into volumetric work and into qualitative analysis. In these courses the development of the structural principle takes the form of greater emphasis on the relation of structure to solubility, of structure to degree of ionization of weak electrolytes, general acid-base theory, relation of structure to color of indicators, and so on. In the third year we give organic chemistry. It is placed here rather than in the second year because the carry-over of'specific information (as distinguished from ideas and concepts) from the general to the analytical course is greater than that to the organic; hence, the student fixes much of the descriptive material before it is completely lost.
AUGUST, 1947
In the organic course we find, in general, the most flagrant failure to build on the general course. There is little carry-over of specific information and nnfortunately, all too frequently, some of the important concepts developed in the first course are never resurrected and built upon. Our organic course might well be subtitled The Chemistry of Covalent Compounds. Here is the chance to. develop the structure principle to the Sit-and I mean structure in terms of atoms and electrons, not just graphic formulas. Because of the fundamental nature of our general course we are able to present organic chemistry in terms of the experimentally determined architectural details of molecules. Knowledge of wave mechanics is not necessary to introduce such fundamental concepts as resonance energy and its effect on stability and activity, and other physical i n d chemical properties of molecules. Instead of studying individual compounds or even individual families, we stress continually the comparison of the properties of the memhers of one family ~ & those h of all families previously studied. Students find this approach fascinating and they find that frequent.1~ they can predict the products of many of the traditional typereactions on which so much time is ordinarily spent. One difficulty is the f a c t that; there is still a lack of textbooks in which these ideas are developed adequately and applied consistently. This indicates that the outlined presentation is still not' common in our universities. The fourth course in the series is the usual physical chemistry. In this course a conscious effort is made to synthesize and integrate all the information from the preceding courses, along with as much as possible of the physics and mathematics. Calculus is used freely. There are no incidental or specialized courses in our undergraduate program. Students do not have time for them anyway. Our aim is not to turn out students with 50 or 60 credit hours in chemistry but merely broadly cultured chemistry majors with 30-odd'hours of chemistry and a solid foundation of physics and mdhematics, as well as a good exposure to languages, literature;and philosophy. We do have, however, special work, practically always without formal credit, for particularly able and ambitious students. They can learn special techniques, such as glass blowing, and can undertake a modest research problem in their senior year. Also, we are developing a course in bio- and physiological chemistry to be taken as an elective in the senior year, but this is still in the discussion stage. A few additional comments d l forestall many questions and objections. Our aim is to prepare men adequately for the best graduate schools of chemistry or medicine. The program is admittedly difficult; it turns out more majors in sociology and Spanish than it does in chemistry. We have the complete support of the administration in upholding the necessary standards of excellence. The most troublesome point is the quantitative aualysis. We have difficulty in completing the amount of x~orkwe want to do. A follow-up course in more ad-
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vanced techniques is greatly to be desired. We accomplish part of this hy includmg colorimetric and potentiometric determinations in the laboratory work in physical chemistry, but more should still be done. The general chemistry laboratory work is a perpetual source of concern and will remain so until someone invents a desk-model cyclotron to be stocked in each freshman locker. During the month or more when atomic structure is the sole topic of the lectures we use the laboratory period for slide-rule drill, for quantitative study of physical properties, for illustration of the Law of Definite Proportionsand similar experiments, but a satisfactory program has not yet been found. We are working to develop a set of experiments that will illustrate the significant points in an interesting way, that will be as different as possible from the experiments most of the students have done in high school, that will challenge the student's powers of observation and .deduction, and that will be feasible for use in large laboraory sections. It's quite an undertaking. Someone is sure to object that beginning with the structure of matter requires the student to accept information on faith rather than to develop concepts from the original experimental observations-it is deductive rather than inductive and therefore is contrary to the way in which science normally advances. This is a fundamental conflict that wemeet in all branches of science teaching. The scientific method involves a definite sequence of four mental operations: collection of information by controlled experiment, inductive synthesis of the information into a generalization or theory or picture, deductive prediction from the generalization, and experimental verification of the deZuction. Ideally we should have our students repeat this procedure under their own power many times during each course. But we run into trouble in the second step. There are no rules for inductive thinking-it occurs, if a t all, as a flash of insight-and so there is no way, to get our students past this hurdle except to lift themover--that is, present them with the generalization. Given the concept, however, most students can make fair predictions and some can devise experimental methods of checking. Hence we may as well start with the generalization and make of that what we can. In conclusion, we must remembw that lack of integration is not far removed from disintegration. Texthooks have been growing by accretion since the days of Lavoisier until some are now approaching'a thousand pages in size. Everything new has been included and too little of the old has been left out. Even atomic bombs have not blasted phlogiston out of all of the freshman texts. Unless a guiding principle is adopted and extraneous material sloughed off, our undergraduate courses mill soon become completely unmanageable. It is high time that we select the fundamentals and hammer away a t them, deliberately, repeatedly, ,persistently. There are few ills in the college chemistry program that cannot be cured by enthusiastic, informed instructors who focus their attention on developing the student and working for his greatest future good.
