Chemistry for antiscience students: A "great conversation" in chemistry

A “Great Conversation'' in Chemistry. Albert E. Finholt and Gary L. Miessler. St. Olaf College, Northfield, MN 55057. Many teaching developments in ...
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Chemistry for Antiscience Students A "Great Conversation" in Chemistry Albell E. Finholl and Gary L. Miessler St. Olaf College, Northfield, MN 55057 Many teaching developments in general chemistry have been directed in recent vears toward nonscience students as consumers and concerned citizens or toward studen- whose bnckgrounds or aptitudes are deficient ( 1 ) . There arc other nonscience majors who receive less attention because they seldom find their way into our physical science classes. These students consider science to he a comparatively unimportant part of the curriculum or an evil to he endured. Occasionally we can lure these recalcitrants into a sugarcoated course if we promise to talk about science and science annlications with a minimum of mathematics. T o them "6;antitative" is a pejorative word. These students are more comfortable if a required science course is free from the usual logic, symbolism, and course content of traditional chemistry and physics. There is somewhat greater enthusiasm for &thing that is more qualitative, such as biology or geology. Perhaps the most notable effort t o teach a general education course in the physical sciences for nonmajors was outlined several decades aeo in the famous "Harvard Case Histories in Experimental Science" (2).Case 2, "The Overthrow of the Phlogiston Theory", by James Conant, and Case 4, "The Atomic-Molecular Theory", by Leonard Nash, remain superb historical tools for teaching chemistrv. One limitation of early chemical history, however, is the absence of modern science with its relevance and its excitement. At the time of the Vietnam unrest, Cassidy cited the harriers that exist between science and our culture. He reported on a physical science course designed to narrow the gap between science and society and to show nonscientists what science has to offer to the intellect (3). A more recent attemnt to integrate science and the humanities has been described by Labianca who combined the use of novels with aoorooriate chemistry topics such as pollution and drugs (4): kltLough the literature contains manv other articles on science in general education, u,e wish t(;describe a course that departs i n m most other teaching formats u,ith an explicit introduction of epistrmological issues, which are then devehped both in the context of the historical development of chemistry and in their relevance t o modern chemistry. During the past two years a t St. Olaf College we have faced the challenge of teaching chemistry as part of a two-year general education program called "The Great Conversation". "The Great Conversation" is a six-course program (one course during each term of St. Olafs 4-1-4 academic calendar for students in their freshman and sophomore years), which consists primarily of a great-books sequence in the humanities, covering the period from the ancient Greeks to the middle of the 19th century. Whereas faculty in this program are mostly from the humanities, students may he from any major; they receive a variety of distribution credits for their participation. I t had been hoped by the designers of the program that we could developa science format that would integrate chemistry in an intimate way into every part of a six-course sequence. Unfortunately, modern chemistry would be eliminated by a time frame that stopped in the 19th century. We compromised by adopting some of the forms and spirit of the humanities courses into a separate physical science unit. The course that emerged seemed to he workable and enjoyable for students and faculty. The last

sentence is presented with reservation because i t is easy to underestimate the lastinr antinathv some individuals feel ~ toward science. One student stated before classes began, "I took all the science I ever want to see in hieh school. I do not want chemistry, and I certainly do not want a laboratory". This typical reaction came from a very bright, able sophomore. We began to teach this group with trepidation. Our course, "Drama and Change in Chemistry". was taught with a laboratory as the fifth course in " ~ i Great e Conversation" sequence, during a one-month Januarv interim. In accordancewith college policy, students were allowed to take only one course during the interim; consequently our assignments were designed to take advantage of the "fulltime" attention that students were to give to our course. We also had freedom to schedule voluntarv extra activities such as field trips, movies, and dinner meetings withguest discussion leaders. Students were informed a t the start of the course that we would present science within the l a r ~ eframework r of philosophy. Anna Harrison has stated that "students with limited experience move with confidence from the specific to the general" ( 5 ) .This approach may be hest t , r &me students, hut it has been our rxperience that it is less attractive for good humanities students or the best science majors. We did not use Gowin Vee mapping in the formal sense described by h v a k ( 6 ) .but we did use the hierarchical strurtures that he proposes. Students need to know the general concepts and the background out of which any intellectual endeavor arises. Without that proper foundation, scientific ohservations and exneriments seem to lead to insienificant sense data, minor bits of trivia compared with the great questions of truth, beauty, and ethics. We wanted everyone, eventually, to share in understanding the significanceif the practical applications of chemistry and to feel the appeal of the sights, sounds, and smell of the laboratory, but we did not wish to begin with specific phenomena. We also wanted the science that we were teaching to have rigor and depth for limited hut important areas of chemistry.

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Course Content The first week of the course was devoted to reading and discussing Kuhn's classic book, "The Structure of ~ c i e h f i c t~evolutions"(7). After one orientation lecture on philosophy of science, the rest of the class time was devoted to small-group (10-15 students per group) discussions of Kuhn. A study guide was distributed with questions and comments on the text; a glossary was added for unfamiliar terms in Kuhn such as auantum mechanics., narallax., Levden jar, neutrino, and cathode rays. More extensive presentations were givenon afew topics such as "Lieht"and "Phlogiston". prior to each discu&on session st;dents were required to turn in 200 to 300 typewritten words on a significant topic in the assigned portion of the text. The students were accustomed to extensive writing in "The Great conversation"^^ the writing chore did not seem out of line. 'I'he flavor of this part of the course can best he seen from a few of the discussion queitions: "Is a paradigm a model or isn't it'!" "If acienre is a orocess for findinr somethine" new.. why is an anomaly unexpected?" "Why isdiscovery a pro-

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cess and not an event?" "What is meant by the 'unhistorical spirit of the scientific community'?" "What do we mean by progress?" "What are the bases for claiming a new paradiem?" The emuhasis in this Dart of the course was on u understanding what Kuhn means by "paradigm" and "scientific revolution". These topics were picked up by the humanities professors teaching later parts of "The Great Conversation" so that students might reach a broader understanding of the term "revolution". The first week thus developed the philoso~hicalsetting .into which the balance of the course was placed. The second week of the course took up origins of the atomic theory, a speriiic paradigm disrussed ~ x t ~ n s i v eby ly Kuhn. l'hr text u,as the first 66 pages of N a s h ' ~case study (81.After one historical lecture that trared the idea of the atoms back to the ancient Greeks, teaching was done by short lectures and discussion sessions. At this noint traditional chemistry was introduced. It is not possible to understand Nash without also understanding- the -cas laws, empirical and true formulas, equations, and weight-to-wiight problems. Stoichiometry came in by necessity; numerical problem-solving began. An effort was made to limit the problems to the minimum degree of difficulty commensurate with understanding the concepts in Nash. Nash's book remains one of the very best texts to help students appreciate the genius and the human limitations of the early pioneers in chemistry. His extensive use of quotations from primary sources, with the distinct language of the 18th and 19th centuries, presents a slice of intellectual history that goes beyond chemistry. The third week of the course was very traditional and possihlv for that reason was the least well accepted by our nonsci&tists. A series of lectures was given that traced the development of modern ideas about bonding and valence in terms of the role of the electron and the at& We tried to make clear that the application of the atomic paradigm to the chemical bond is a significant example of the "articulation of the paradigm theory" leading to what Kuhn calls the "puzzle-solving" capacity of "normal science". Readings were assigned, with problems, from "Fundamentals of Chemistrv" hv Bradv and Holum (9).The text received a good respo&e, hut thimaterinl ansct)nsldered by many students 10 be difficult. The level of this Dart of the course mas have been too high, but we wanted to show the scientist as amodel builder and not just as a collector of facts. A few members of the class just t&ew up their hands in dismay, but the rest, with effort, did a reasonable job of mastering the chemistry. A different kind of respect for science began to emerge. The final part of the course was an introduction to organic chemistrv. bv . wav. of the alkanes and alkenes. includine an introduction to isomerism. The atomic paradigm was shown to lead to practical applications and unexpected novelty. The importance of spatial ideas was emphasized in a discussion of addition and condensation polvmers and an introduction to nucleic acids and replication. Selections from Brady and Holum were again used as a text, and teaching was the usual combination of lectures and discussions. Laboratory

Above all, we wanted the laboratory to he fun. We knew that a hieh uercentaee of the students had no feeline for the the laboratory brings to mostexperikind of Gjoiment mental scientists. Somehow. somewhere. enthusiasm for experimentation had been destroyed or just not experienced in earlier science courses. T o relieve anxietv. the laboratorv was graded "passlno credit," hut 100% attendance was insured by a penalty of 5%of the course grade for any unexcused absence. Seven laboratory periods were scheduled. The experiments were not new, hut they were carefully chosen to stimulate thought, to demonstrate the role of the laboratory in science, and to repeat some historically impor-

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tant experiments. Our oral and written introduction to each exneriment emuhasized the wavin which facts are tied to the atomic theory. The assignments included: 1) The "Blue Bottle" experiment. The famous J. Arthur Camp-

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bell combination of observation and deduction (10) was a good beginning for students with no background in chemistry. They responded well with the usual reactions of bewilderment and curiosity. Measuring the Length of a Molecule. A monomolecular layer of stearic acid was prepared by allowing a cyclohexane solution containing a known concentration of stearic acid to evaporate on an aqueous surface. By measuring the surface area of this layer with a ruler, students were able, by a simple calculation, to determine the length of the molecule. This is an excellent demonstration of the scientific way to get information which cannot be obtained directly (11). Combimng We~ghts(Magnesium plus Oxygen). Auogardo's Law. Some of the experimental work of Dalton and Gav-Lussac was reoroduced bv. weiehine bulbs filled with hvdrugen, oxvgen, and nitrogen. (Nitrous oxide was usrd as an "unknown", srudrnts urre askrd ro derrrminr irs rrlntive weight based on chc assumptions of i)olton and Gay-l.ussnc.) Air was used as a reference gas to obtain relative molecular weights. This laboratory helped make clear much of the material in Nash. Isomers. Students worked in pairs to make models of assigned geometric and optical isomers. Most of this laboratory dealt with the usual organic isomers,hut octahedralcomplexes with and without chelation were included. Polarimetry and NMR were demonstrated. Wohler's Synthesis of Artificial Urea (12). Polymers. Polyesters and nylon were prepared with a brief study of their properties (13).

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Evaluation

On the basis of student evaluations, the course was well received. There was a sliehtlv . hieher deeree of annroval in the second year, perhapsubecause of extksive rewriting of course materials and the benefit for us of one year of experience. In the first year 40% of the students emerged feeling more nositive toward science: this rose to 50% in the second year. 'Another 20-30'3 entered the course with a positive attitude, and they remained positive. The laboratory was rated excellent or very good by 58%of the students the first sear and by 71% of the students the second year. An excellent or very good overall reaction to the course was given by 61%of the students the first year and by 71% of the students the second vear. Almost all of the students considered the work load to be reasonable and comparable to the other narts of "The Great Conversation". I t was not our goal to convert students into scientists, and there is little doubt that we did not erase a ureference bv many students for word symbols rather than f i r scientific or mathematical symbols. I t was gratifying, however, to have some students tell us, albeit even grudgingly, that they had come to understand whv people .. - are attracted to the iutellectual challenge of the sciences. Teaching a respect for science is a t least as important as teaching.the practical benefits of science. It was our good fortune to have some of the humanities professors audit the course with active participation in the discussions and even the laboratory. They made invaluable sueeestions. and fortunatelv for our morale thev liked much of what they saw and heard. Some comments were revealing. One professor lamented that no courses like this were available when he had to satisfy his science requirements in college. An English professor was surprised a t the amount of detailed instruction that we put into the laboratory manual. We suggested that he look around and see how much trouble the students were having with our "clear" instructions. The Kuhn and Nash parts of the course had the strongest appeal for most of our students regardless of their interest and background. The overall high acceptability of the course

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probably can he attributed to the philosophical introduction, which enabled us to show the many ways that chemistry embodies the concept and strategy of the atomic paradigm. Students were more comfortable with a science that was linked to thought processes encountered in other parts of the curriculum. We did demonstrate that one can take a class that includes a high percentage of nonscience and even antiscience students and still teach chemical theory as well as history, philosophy, and descriptive material. Admittedly, our students were not from the lower academic strata, hut neither were they by intention or self-selection solely from the top end of the scale. Our course material was not esoteric, hut it was a different kind of a package than is normally presented, and it worked.

Llterature Cited SOP,for example, Ham, R. J. Cham. Edur. 1980,57, 490, and Middlmamp, C. H.: Kesn, E. J. Cham. Edue 1983.60.960. Conant. J. "Haward Case Histories in Experimental Science": Haward University: Cambridge, MA. 1957. Csssidy,H. G.J. Chrm. Educ. 19'71.48,212. Labianca,D. A.J . Chem.Educ. 1984,61,148. Harrison, A. J. J. Chem. Educ. 1982.69. 713. N0vak.J. O.J. Chem.Edue. 1984.61.607. Kuhn,T. S."The StrunureafScientificRevolufions",2nded.;UniversityofChieago: Chicago, 1970. Nash. L. K. "The Atomic-Molecular Theory":ref. 2, p 215. Rrady, J. E.: Holm. J. R. "FundamentalsofChemisf~";Wiley: New York, 1981. Csmpbell, J. A. "Why Do Chemiesl Reactions Occur?"; Prentice-Hall:Englwood

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