Revolutionary chemistry. A new kind of chemistry course for the

Revolutionary chemistry. A new kind of chemistry course for the nonscience majors. Robert West. J. Chem. Educ. , 1971, 48 (10), p 648. DOI: 10.1021/ ...
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Chemistry and Social Concern

Robert West

The University of Wisconsin Madison, Wisconsin 53706

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Revdutionary Chemistry A new kind o f chemistry course for nonscience majors

In this paper various approaches to the education of nonscience students in chemistry are described, and the experimental chemistry course which weare offering at theuniversity of Wisconsin is discussed in detail. The paper will begin, however, with some general comments on college chemistry curricula. The Trouble with General Chemistry

Probably chemistry leads all other fields of science in the amount of attention and effort which has been devoted to the curriculum. Chemistry courses are usually thoughtfully planned as to content, and carefully sequenced so that what has been taught in one course is (in principle anyway) utilized, expanded upon, or covered a t a higher level of understanding in succeeding courses. As a result, professional training of chemists in the United States is generally satisfactory. Graduate schools, and employers of chemists, are able to assume an extensive common background of knowledge on the part of BS chemistry graduates from quite diverse institutions. In spite of the fact that the professional training of chemistry is already rather good, it is this part of chemical education-the professional curriculumwhich has received the overwhelming emphasis in modifications of chemical education over the past fifteen years. Surprisingly little constructive thought hn.s heen given t,n providing an appropriate education in chemistry for the vast majority of students who will not be professional scientists of any sort. Courses in "general chemistry" will have changed somewhat over the past 15 years; they now include much more physico-chemical theory, and rather less descriptive chemistry. But with very few exceptions, general chemistry textbooks today cover the same topics which have, by common agreement, been accepted for years as part of the first year professional training for chemists. And the coverage is usually the same for general chemistry courses even if the committed chemistry majors .are selected out into a special, high-level introductory course! Several rationalizations are offeredfor the teaching of an essentially professional course in general chemistry to all students, rather than just to professional science students. The first is an "on principle" argument,: There is "only one kind of chemistry," which should therefore he taught to everyone; traditional general chemistry, which has served us so well, should not be "watered down" or "diluted" to serve the interests of nonscicncc studcnts. A sccond argument is more pragmatic: The general chemistry course serves to recruit undecided students into chemistry, and a pro648

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fessional course should be offered to everyone so that this recruitment can be accomplished without loss of time. The first argument implicitly assumes that a course leaving out most of traditional general chemistry would not be intellectually demanding;' I believe this assumption can easily be shown false. The second argument alone would justify designing the entire introductory course in chemistry to serve the needs ol a small minority, a procedure which seems unfair on its face. It is true that some students are recruited into chemistry from general chemistry courses, but nowadays the vast majority of freshmen students h o w whether they are headed toward professional study of physical sciences or toward some other field.% Carcfully considered, the arguments for traditional general chemistry for all students smack of self-serving rationalizations. Why have chemists been so slow to develop innovative approaches to the teaching of chemistry to nonscience students? The causes are multiple, but important among t,hpm is t h e ov~rprofessionalisedreward system which has come to dominate science faculties at the Universities, according to which tenure, prestige, financial rewards, special privileges, and job mobility are granted to the scientist who is successful in research rather than to the effective teacher. In recruiting and retaining faculty, research productivity and promise is given primary consideration, so the system tends to be self-prepetuatiug, I t is truly surprising to what extent this research ethic has pervaded even the liberal arts colleges, where, if anywhere, we might expect people to know better. Accordingly, graduate training and iesearch receive the greatest emphasis; and claim on faculty time from professionalundergraduate training is second, and education of nonscientists, a poor third. At some institutions, the service courses in general chemistry are assigned to the least creative members of the faculty;at others they are taught grudgingly by research scholars whose minds are largely elsewhere, with the help of large - cadres of poorly-trained graduate assistanis. The description given applies to the situation as it was, and st,ill is in many placcs; hut note that things are now changing. Many if not most colleges and 'In fact "revolutionary chemistry" and similar courses require less mathematiczl pproblemaolving and memoriaa.tion than traditional courses, hot are more demanding than traditional courses in other ways. %Theargument that chemistry courses should be designed ta recruit students into chemistry was never particdarly compelling, and loses additional force now that there is an oversupply of chemists. For that matter, it is not even dear that a traditional course would be the best means for recruiting undecided students.

Chemistry and Social Concern universities are now offering, or planning to offer, introductory courses for nonscience students.which differ substantially from traditional general chemistry. Why are innovations being considered now, when they might as well have been introduced a decade ago? The main spur, come8 from the students themselves. Students today are much more concerned with social problems than they have been in the past, and much less patient with courses of study which do not seem "relevant." Colleges are responding to students demands, voiced with increasing militance, for courses which deal with their needs and interests as they perceive them. Also, some faculty members are genuinely concerned with the bad effectsof unbridled technology on the environment, and with the increasingly hostile view of science among the general public. To these motivations for more relevant chemistry courses may soon he added a third: Many colleges may give up requirements in physical sciences, so the "general chemistry" will lose much of its captive audience and will have to attract students on its merits and interest! Some N e w Approaches

If chemistry for nonscience students is to he freed of its traditional bonds, what new sort of course might be designed? Actually, several kinda of courses are possible. These will be classified arbitrarily as: 1) historical; 2) philosophical; 3) social-environmental, of which my own course at Wisconsin is an example. Let us now consider these briefly in turn. The historical approach to teaching of chemistry represents the earliest attempt to design a special chemistry course for liheral arts students. A6 early as fifteen years ago, Leonard Nash pioneered the use of historical caye studies in teaching chemistry at Harvard. Teaching of the chemistry part of "general studies" programs for liberal arts students has often fallen to the lot of historians of chemistry, and so the historical approach has been tried a t various colleges. The history of chemistry is a worthwhile subject in its own right,s hut in my opinion it is a relatively poor vehicle for education of nonscience students today, for several reasons. First, the history of science, however well taught, does not lead students to an understanding of the way modern technology actually operates, and so does not allow them to "come to grips with their environment." For this, it is clearly necessary to have information about science as we now understand it. Second, students today are impatient with the historical approach and indeed even anti-historical in their attitudes. They are turned off by discussions of how John Dalton deduced the existence of atoms. They already know perfectly well that atoms exist. A skillful teacher might he able to arouse their interest in the history of chemistry, after a time, but it seems much more efficient to start with existing motivation than to develop it as the course proceeds. The "philosophical" approach to teaching science has been more favored by physics than by chemistry faculties, and some kind of "physics for poets" is offered with varying success a t several universities. Some fascinating topics could he discussed in a philosophical chemistry course: the significance of entropy in ordering time, the indeterminacy principle, the origin of life,

etc. However, the philosophical approach suffers from the same disadvantages as the historical: It does not attempt to lead the student to an understanding of modern chemistry as we know it, and it does not start with existing motivation. The third approach emphasizing application of chemistry to social and environmental problems has the tremendous advantage of built-in motivation on the part of the students. Moreover, this orientation leads to learning precisely those aspects of chemistry most useful to nonscientists. Some courses of this kind begin with considerations of important problems-nuclear warfare, air pollution, or drug abuse for example-and bring in chemistry and other sciences only as they appear to be necessary to the particular problem under discussion. Courses following this plan can be extremely successful-a good example is the course taught by Professor James Boggs a t the University of Texas. The only disadvantage of this plan-and to my mind it is a serious one-is that the learning of solid chemistry tends to he too loose and unstrnctured to he intellectually satisfying. At Wisconsin we have followed a slightly diierent plan, in which study of selected aspects of chemistry proceeds at the same time as consideration of social problems. "Revolutionary Chemistry7'-The Wisconsin Course

Chemistry 181, the course a t Wisconsin which has been nicknamed "revolutionary chemistry," was first offered in the fall of 1969-70 and is being repeated this fall with 60 students registered. The course carries honors credit, and so is taken by relatively well-prepared students, all of whom have taken high school chemistry and a t least 2 years of high school mathematics. The course met six times a week, for three lectures, two recitations and a 3-hr laboratory. Recitation and laboratory sections contained about 15 students each. General Plan

The aspects of chemistry which seem to me to be most relevant to contemporary problems and to have tbe greatest impact on the lives of ordinary citizens are organic chemistry, biochemistry (i.e., "molecular biology"), and nuclear chemistry. These were selected for emphasis; by eliminating everything else from canventional general chemistry except a. brief introduction to atomic structure and chemical bonding, these three main topics could be treated in some depth. The organic and biochemical parts were tied together through the central idea of molecular structure and architecture.' An outline of the course is given in the table. Since Chemistry 181 was not serving professional chemistry students, it was unnecessary to cover the traditional general chemistry topics in order to prepare students for further courses in chemistry. However, the students were asked to review, or master, the concepts of stoichiometry, ionio equilibria, and acidbase properties by individual study of programmed readers during the first few weeks. This individual study highly suc. proved . cessful. Paperback books were used as the only texts. Five were on chemical topics, replacing the conventional textbook. Five books on more general topies relating to science and society were also ~

81ndeed, the history of science and technology has been neglected relative to other historical fields. The emphasis on pre1900 science by historians also seems unfortunate, since most science has actually "happened" in the 20th century. ' About 60% of the time in lectures and recitations was devoted to these chemical topics, and about 40% to applications of these topics to social and environmental problems. Volume 48, Number 10, October 1971

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Chemistry and Social Concern Outline for Chemistrv 181 Topica

11. Ownnia Chcmidry (6 weeks) Alkanes, alkenes. slkyner; substitution and addition: isomerism; petroleum chemistry and polities: hromhtie compounds and bonding: aloohols: oarhonyl compounds; nitrogen oomoounds: inaecticider; pest control; psychoactive drugs: chair reactions: polymers and plaatios; water pollution 111. Biochemiatrg (4 weeks) Fats and oils; carbohydrates: carbohydrate metabolism: oellular anergy produetion: amino adds; proteins; purines and pyrimidines: nueleio acids: protein synthesis; replication; steroid hormones; chemistry o i reproduction and contraception; modes o i drug action

Texts

supplements): WASON. "Double Helix." Exme.. H. D., "Introduction,to the Chemistry of Life: Organlo Chemistry": Coow, P. L., A N D Cnunr~,J. W.. "Organic Chemistry: A Contemporary view"; CARSON. RACHEL. "Silent Spring"; RIENOW, R., *xo Rmaow. L. T., "Moment in the Sun."

D m m , H. J., "Introduction to the Chemistry of Life: Biaohemistry": EHRLICH. P., "The Population Bomb."

detection of radiosotivity: natural radioaotive series: artificial radioaotivitv: fission: nuclear reactors: synthstio elements; nuclear energy; fusion; power sources; nuclear weapons

assigned, and at appropriate times during thesemester these readings were discussed in recitation sections, often with a student as discussion leader. A number of outside speakers on topics relating science to social problems also met with the class for lecture-discussions during the semester. Several other techniques were used to increase the relevance of the course to social prohlems. I n lieu of a final examination students were offered the option of writing a term paper, and of the students did so. Many of these were on socialahout technological problems such as chemical warfare, pollution control, etc. To aid in writing these papers, as well as for additional reading, a special collection of books on social issues having some scientific component was assembled and made available in the chemistry library. Numerous articles, reprints, and mimeographed supplements on sociotechnologieal problems were distributed or placed in the library collection. Flexibility was maintained in the lectures so that topics arousing especial interest could be treated in more depth. Newsworthy items were discussed as they happened (mercury pollution, the cyclamate ban, the Nobel Prizes for carbohydrate hiosynthesis, the isolation of the lac operon gene, ete.). Finally, at the etudents' suggestion biweekly optional meetings were arranged where instructors and interested students met over coffee to discuss broad social and technological issues. These meetings were not structured but each was mainly devoted to a single idea or problem. Topics discussed included "militarism," Federal support of the University, chemical and biological warfare, the purposes of a university, laws on contrsceptian and ahorlion, psychedelic drugs, etc. By their attitudes the instructors managed to decouple the motivation of students from the usual coercive pressure of grades -though this might have been done even mare suecessfullv if the course were graded on a pass-fail basis. By freeing student motivation some unusual and highly involving types of learning took place. For example, two sections held afascinating debate on the question "population limitation versus industrialization in the underdeveloped world." Another section held an inquiry into the military connection with science at the university, inviting various staff and students to "testify." The whole course, instructors and students, cooperated in holding an "environmental fair" a t which films and sound-slide shows were presented, art works by students on environmental topics were displayed, etc. The laboratory was completely revised in order to fit the new

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pattern of the course, and in most cases was more relevant. The first experiment was determination of hardness of Madison water by EDTA titration, followed by titration of a detergent sample for ~ h o s ~ h aconvent, te with students obtaining their own samnlm of detergents. Eightlaboratory sessions were then d e v o t e z z orgmic chemistry. Each student spent about 4 weeks on experiments in organic syntheses and identification, and 4 weeks studying the separation of hydrocarbons by gas chromatography, leading to eventuel identification and determination of the principal hydroearbonr in commercial gasoline samples obtained individually from service stations. This project was of a "research" nature, and generated much student interest, as well as leading to some fascinating results. (Sections were split, some doing organic synthesk first before gas chromatography and vice versa, to reduce crowding on chromatographs.) Another consumeroriented exueriment followed, in which students obtained s a m ~ l e s of margarines, cooking fats, etc. and determined the amoun& of saturated and unsaturated fatty acids in their sample by gas chromatography. The second biochemical experiment was s. speotrophotometric analysis of glucose in blood. This is being done as a group project, with student volunteers as suhjeots. Finally a neutron activation and counting experiment is carried out using a neutron source and Geiger-Muller counter. Evaluation ond Recommendations

The student resDonse to Chemistrv 181 was strikinelv -" and overwhelmingly enthusiastic. Only by teaching a course of this kind can one really appreciate the intense concern students have for environmental and related social problems and the tremendous motivational force for learning which this provides. A course with the objects of Chemistry 181 should be carefully designed to meet the needs of the particular students. Methods successful with our honors students would certainly require modification for use with a more heterogeneous group, for instance. However, the spectacular response to Chemistry 181 leads me to helieve that any thoroughgoing attempt to relate general chemistry to social problems is likely to meet with great success. Courses emphasizing the relationship of chemistry to social problems may not be the best introduction for students planning careers in science, hut seem highly desirable for others who will s i m ~ l vbe citizens. Chemistry 181 has alreadv neneratei over 200 reauests for infirmation from othe;colleges and universi&es. My guess is that most chemistry courses for nonrnajors will gradually develop in the direction of Chemistry 181. However, the difficulties of this approach should not he underestimated. The course is expensive in planning time, instructional time, and materials. Small sections were deemed necessary both for informal discussions and for the specialized laboratory. Unusual maturity on the part of teaching assistants is most important. In selecting assistants, particularly intelligent graduate students with broad interests and the desire to participate in an unusual teaching experience were sought. (There will never be enough such people, but their number may be increasing.) Just the simple matter of spreading information about a new course may present difficulties, especially at a large institution. The course as we gave it is demanding and involving for all of the instructional staff, but we feel the results more than justify the added effort. Those who would like additional information or encouragement are invited to write to the author.