A relevant liberal arts chemistry course - Journal of Chemical

Presents what the author regards as a relevant liberal arts course, one ... Chemistry as General Education ... Journal of Chemical Education 2004 81 (...
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A Relevant liberal Arts Chemistry Course

At the University of South Florida we have felt for some time that a response to the plea for relevance is mandatory in academia. We feel that freshmen chemistry does not serve the function of a relevant liberal arts elective for non-science majors. There are many reasons for this: Freshman Chemistry is "inherently" difficult and requires an inordinate amount of mathematical preparation for the nonscientist. Perhaps a more fundamental reason, however, is that freshman chemistry is concerned primarily with the preparation of students to pursue more advanced chemistry courses. As a result, there is rarely time to discuss interesting developments of modern chemistry, let alone history and philosophy of the scientific enterprise. Our answer to this problem has been to institute a new course which we call Modem Chemical Science, CHM 371. Enrollment is open only to students who have had no more than high school chemistry and who do not plan to major in science. I have taught the course five t~imesto students in all areas of the University including the liberal arts areas, business, and education. Student response has been uniformly enthusiastic. Our goals in CHM 371 are to provide an appreciation of whet chemistry is as a human pursuit an appreciation of the nature of chemical knowledge and how it is ahtsined the scientific background needed by the individual in making decisions required of a. participating citizen of a technolagicd nation the basic technical vocabulary to understand the accomplishments of chemistry and their meaning to man

The problems of existing freshman chemistry courses in meeting the above goals are too much emphasis an the manipulative tools, techniques, and mathematical drill too much emphasis on covering the material necessary to prepare students for subsequent courses too much emphasis on the theoretical and quantitative, s t the expense of the observable and descriptive not enough attention to the way in which chemists approach their research and carry it through-the purely personal and emotional aspects of the science

Freshman chemistry has evolved into an excellent example of "textbook science": a clear, concise, orderly presentation of subjeds that are developed logically one from another. As we all know, this approach to textbook writing is necessitated by the enormous quantity of material that must be presented. But in the efficient exposition of the totality of chemistry in a one year course, a very important aspect of the subject is lost (actually, worse than that; it is misrepresented); vie., a description of how research is done and of the way in which chemistry develops. Thus, there are two chemistries: "Textbook Chemistry" and "Research 624

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lournal of Chemical Education

Chemistry." That there is a great difference between these two chemistries is evident from the all too common situation in which the student emerges from a chemistry course bored and worn down while the professor emerges thinking that his work is thoroughly engrossing and exciting. Can these two people have been involved in the same activity? Thus the main goals of a course for non-scientists should be accomplished by a study of "Research Chemistry" and by minimizing the approach of "Textbook Chemistry." I have tried to do this (and in fact, have prepared a textbook for the subject) by a partly historical approach in which a balance of depth and breadth is sought. I ask the students in my classes not only to know the facts, concepts, and theories presented, but also to understand them. While this might seem too ambitious a task for non-science majors, such has not been the case in my experience under the proper conditions. In the first place, the understanding of only a few ideas is undertaken. Secondly, by understanding is meant that the student should be aware of the experimental background of a theory and its relationship to the theory and to possible alternate theories. It is next to useless for a student to "know" that atoms consist of electrons, protons, and neutrons, if he is not aware of the experiments that led to this model. What teacher has not heard the student's complaint that what he learned last year is now wrong. Even a cursory understanding of the experimental background can provide the student with the awareness that each theory has its level of credibility. It is this understanding that a theory has less than 100yo credibility that lends it relevance. I n fact, it has often been this very uncertainty that has spurred further research resulting in leaps in scientific knowledge. An appreciation that chemistry is a human activity governed by an underlying philosophy is the main objective of our CHAI 371. The vehicle through which this objective is pursued forms the subject matter of the course. I n CHM 371, chemistry is developed in terms of two broad chemical concepts ( 1 ) The relationship between atomio-molecular structure and ex-

perimentally observable properties of substances-the concept of the mleeule (2) The nature of chemical chsng-the concept of the chemical reactin

Under (1) are discussed gases and the kineticmolecular theory, atomic structure, chemical bonding, valence, periodicity, molecular architecture, nuclear chemistry, polymer chemistry, the chemistry of life, and biologically active substances. Under (2) are discussed qualitatively energy, the statistical nature of

chemistry and energy, chemical reactions, equilibrium, mechanisms, and some technologically important processes. Specifically, the general scheme has been to lay the experimental foundation before presenting the theoretical. The foundation for molecules is laid through a brief introduction to the qualitative behavior of gases. The foundation for chemical bonding is laid upon an observable physical criterion (electrical conductivity) for bond type. This is followed by an examination of the differences between ionic and covalent substances, and a correlation of bond type with periodicity. The evolution of atomic theory through concepts of quantum mechanics is then developed briefly. I n the examination of molecular architecture we survey the variations in molecular structure that are possible in covalent molecules and raise questions concerning the physical consequences of these structures. These consequences include chemical energy, stability, and physical and chemical properties. The chemist's analytical tools are explored through a conceptual t r e a h e n t of the principles upon which spectrophotometric and X-ray analyses are based. The concept of chemical reactions is briefly presented primarily to offer an appreciation of the challenges and accomplishments of synthetic chemistry and chemical dynamics. The study of reaction mechanism is introduced as one of the many areas of current chemical research. The concept of equilibrium is then presented along with Faraday's work on electrolysis to expand the concept of chemical dynamics and to present still another confirmation of the atomic-molecular theory. The remaiuiug topics are essentially expansions of previous ones: stereochemical ideas and their practical consequences, a very brief qualitative exposition of the characteristics of organic chemistry and why it is distinguished as a separate branch of chemistry, and some examples of natural products and the relationships between structure and physiological activity. These topics are presented wherever possible through original works; i.e., important papers which can be read by the beginning student, and which give a hint of the tenor of the times when the ideas were new. Many of these ideas are developed historically to emphasize the actual evolution of experiments and the string of conclusions which followed from each.

The novelty of this approach is, I believe, in its attempt to convey the continuity of chemistry. The appeal to students of this approach has been very good. I n fact, many students have diverted their plans to include additional chemistry courses and a few have actually changed to chemistry as their major. Nearly all of the students have expressed surprise that chemistry is quite different from what they had previously thought it to be. It should be noted that students completing CHM 371 and wishing to go on in chemistry must begin freshman chemistry anew since CHM 371 cannot be counted in lieu of any of our major courses. IMoreover, many of my CHM 371 student,s who later went on to take freshman chemistry have expressed the view that CHM 371 provided an excellent background which lent relevance to freshman chemistry; i.e., they knew why the various topics were presented and where they were leading. This brings me to the final point, and t,he one which was somewhat surprising. The goals of CHM 371 as outlined above may very well be the best goals for an introductory course in chemistry. All too often, introductory courses are designed to provide the deficient student with the manipulative mathematical techniques necessary to go on to subsequent courses. This, almost of necessity, means that such a course is doomed largely bo dull, repetitive drill. This is hardly a suitable introduction to the study of the exciting field of chemistry. Wouldn't it be preferable to give the introductory student some idea of the stimulating intellectual rewards to expect from the study of chemistry? Additionally, we owe it to our young potential chemists to let them know what to expect in chemistry as early as possible. We are planning to implement these ideas by introducing a new foundations course in chemistry for student.^ who are poorly prepared to enter our freshman course. Our approach will include many of the ideas discussed above.

J. E. Fernandez of South Florida Tampa, Florida 33620

University

Volume 47, Number 9, September 1970

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