search. As part of an effort to promote a more researchfriendly science curriculum ( l o ) , the second semester course has an additional readinglwrit'mg assignment that addresses the nature of scientific research. Our introduction of the human side of scientific endeavor into the course curriculum is modeled largely after efforts in the Biology Department of Occidental College (11).As an extra-credit project students are provided a biographical account of a scientist that deals with some aspect of science research. Our choices of books in the two years we have carried out this project have been Radiant Science, Dark Politics (12)and Chase, Chance and Creativity (13). Both of these books provide insight into the process of scientific discovery that is well worth reading. They both emphasize in one manner or another the prominent role of creativity in scientific research. The reports that students write are not summaries of the books, but rather essays that are keyed to a more personal exploration of their motivations for studying science. Students are encouraged to write about aspects of science that are brought up in the book that they found surprising. Other themes for papers include comparisons of the student to the scientist who is the biographic subject. Throughout, the overall emphasis and net effect of the assignment is to introduce students to aspects of science they had previously overlooked. This assignment alone appears to have increased the number of students interested in exploring options that might lead to research careers. Moreover, a net increase in chemistry majors appears to have resulted from this assignment. From the standpoint of the depersonalized atmosphere of the course this assignment strikes a substantial blow. By encouraging students to write about their opinions and their own self perceptions the instructor automatically gets to know more about the students. Again the ability to write comments to the students as part of the correcting process increases the personal communications that occur in the course. For some students, this assignment ultimately becomes a threshold event that changes not only their undergraduate career but even their lifetime ambitions. In closing I would like to acknowledge the USD Faculty Development Grant Program for its ongoing support of the project described in this paper Literature Cited 1. National Sdenee Foundation, T h e &isnee and Engineering Pipeline: PRAReport
67-2.April. 1987. 2. %bias, 9. T W r oNot Dumb, T W n f i f i r e n t : S t d k i i g t b &mnd '&?;Research Corpaatian:Tusan, AZ. 1990. 3. GPske,J.Coll. Zh&. 1W2,40.151. 4. Tabias, 8. Rmitalking Undergmduofe Scisio: Reaeareh Carporetion: mmn, AZ, 1992. 5. H0lme.T A J. Cbm. Edue. lm8,inpress 6. H ~ l m eA. ~J. Ckm. Ed=
9. Comer, M. 1Vholk Hoppning in Chemistry; American Chemical Society: NewYork, 1992. 10. Conference theme ofthe 4th Natimal Conference ofthe Council on Undergraduate Reaeareh, Holland MI, 1992. 11. Hmper, L., talk given at mnfemee on "Elements ofResearch lnereaaing Student Engagementin the EntnLevel8eienee Course', S c h e n d y . NY,1991. 12. Kame", M.R d a n t Scisna, Dark Polities: University of Calif-% 1995. Cleotiuily.Co1-bia
Eduardo Jorae Bottani
lnstituto ae inv&igacmonesRs.mq~irnicasTeMcas y Apllcadas (INF TA) Corns on oe lnvesrigaciones C enrlcas de la Prov nca de Buenos Aires (CIC) and Facultad de lngenieria de la UNLP C.C. 16 Suc. 4: RA-1900 La Plata. Argentina The goal of this paper is to describe the changes we have introduced in the general chemistry course for chemical engineering students. During 1988 the Faculty of Engineering decided to update the curricula of all the degrees offered. This decision started a generalized discussion that covered not onlv the contents of each course but also the teaching methodology that were in current use. As a result of this discussion the annual general chemistry course was replaced by two courses, one semester of general chemistry and one semester of inoreanic chemistm. The methodological modification introduced in both courses is based on the idea that it is better to teach increasingly complex models as they are needed rather than to follow the usual practlce of giving all theories, starting with the simolest followed bv more refined treatments. ~-~~~~ ------.. like a historich review. To fully comprehend a given model: students must be able to a ~ o l it v to solve oractical or theoretical problems. ~eforereplacinga n imperfect model with a new one, the student must he convinced of the necessity of this change. Nobody can deny the importance of teaching the atomic structure of matter in general chemistry, but quantum mechanics is not required to understand the subjects generally included in the course. So, why unnecessarily introduce this subject? We certainly did it in the past with several consequences. First we devoted some time to this item to the detriment of other more important subjects, and students could not comprehend its usefulness. Students who could manage quantum numbers did not know or comprehend their meaning, they ignored the origin of quantum numbers, and, finally, they acquired false images of atomic orbitals. It is also true that current textbooks are not so good in this area, but this is not a valid excuse to introduce misconceptions that we must remove later. We moved quantum mechanics from the general chemistry to the inorganic chemistry course where it must be used. In the latter course we devote three classes to introduce quantum mechanics. We start showing some examples that support the necessity of a new theory (quantum mechanics), we solve the problem of the particle in a onedimensional box t o show: how quantum numbers are derived, the meaning of wave f&tions, energy levels, etc. This approach produces a concept that is meanindul to the students and one they can use rationalize some aspects of the behavior of the elements.
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The General Chemistry Course
aeapted forpublication.
7. Dk-m of the iunovatims made by H m c h b b h h be f f f d in refmnmz. 8. H0lmgrrn.P J.CoU. Sei. k h . 1SE+2,21,193.
13. Austin. J. H. Chose, Ch-and
Introducing Chemistry to Chemical Engineering Students
Berkeley, CA.
UrUversity:New York, 1977.
The general chemistry course starts with matter and material systems, atomic structure, chemical bond, gases, liquids, solids, thermodynamics, chemical equilibrium, solutions, colligative properties, chemical kinetics and electrochemistry. The m a t difference. in resoect to the old course. is -~ that ~ now we must teach, & a limikd time, the fundamental of "fundamentals" and the to~icsthat students usuallv -find ---~~ more complex. The course contains three different kind of classes: lectures, seminars, and laboratory experiments.
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In the lectures, more-or-less developed in a classic fashion, the professor presents each topic and describes the main points. During seminars students must solve problems or answer ouestions related to the lecture. This task can be done as homework or during the seminar time. Students mostly prefer to do it as homework and to employ the seminar time to discuss the answers with other students and with the ~rofessor.Students s~ontaneouslvform discussion groups; and the professor does not explicitly give the answers, but he guides them to fmd the answers. Seminars are taken as informal classes where students have more freedom than in a classiclecture, givingto the professor the opportunity to discover their difficulties and to help them in a more personalized way. Laboratory classes consist of selected experiments that enable the students to reinforce the concepts, to acquire the necessary experience in performing basic physicochemical calculations, and to get hands-on experience in a laboratory. Course evaluation is performed at two levels. At the first level teaching assistants evaluate the ability to perform calculations and the performance of students a t the laboratory. The second evaluation is done bv the ~ r o f e s s o r through five cumulative examinations. Basic exams are prepared for all the students. When a student shows difficulties with one or more topics, special questions are added to a subsequent test in order to determine if the difficulties previously encountered have been solved. Once the tests are evaluated, they are discussed with each student during personal interviews in order to mark the topics needed to be reviewed. The Inorganic Chemistry Course The goal of this course is to introduce the student to the studv of chemical and nhvsical nrouerties. as well as the behakor, of the elementk i n this'coirse wemix descriptive inorganic chemistry with structural chemistry in order to minimize the memorization needed in a traditional descriptive course. We begin by developing the basic concepts related to atomic, molecular, and hybrid orbitals. Then l each mu^ of elements is oresented with s ~ e c i aattention to the main properties of the elements bklonging to the group, natural occurrence, isolation, purification, laboratory and industrial preparation methods, the most important compounds and their historic and modem uses, always of the most relevant elements. Environmental aspects are introduced in different parts of the course as an example of the role of chemistry in solving problems; new materials are mentioned in order to show the role of chemistry in the improvement of our life quality; some examples are given where chemistry contributes to the solution of interdisciplinary problems. We take each opportunity to show how chemistry is present in our lives and its social and cultural consequences. The lectures given by the professor are complemented with seminars having the same organization and purposes of those corresponding to the general chemi ~~-t"n course. r -The laboratory is devoted to the preparation and characterization of several elements and their compounds. These activities are comolemented with the oreoiration., bv the students, of mondgraphs that require a relatively simple biblioera~hic - . search. This is done to develoo writ in^ skills and because writing is also a very important activity that contributes to the learnine Drocess. The evaluation of students is decided in the same' way as in the general cbemistry course. Under this new organization, the inadequate physical and mathematical backgrounds usually encountered in our students were partially dealt with by placing the general chemistry course in the second semester of the first &
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career year followed by the inorganic course. The teachine staff is-the same for bbth courses assuring a great degree of content homogeneity and methodological continuity. Another advantage of having the same teaching staff is that we know exactly what we have taught in general chemistry and what le&l the students rearhed: tLerefore, we can introduce minor corrections each year. This aluo avoids the danger of performing drastic changes that usually result in failed experiments with the consequent damage in the formation of our students. We also devote a few minutes - ~ - -~ - ~- at -~~ the beginning of each class to explain the importance of the topics discussed and how thev will relate to tonics that will b'introduced later in the co;rse. For the students the new methodology implies much more personal work than in the past, nevertheless, they do not disamee with it because under this svstem thev nlav a n activerole in the learning process. students are a ~ to attend the seminars with their books and any other source of information that they consider useful. When they spontaneously form working ~ O U D Sthev feel free to express their opinions within thegroup beciuse they are not afraid of making mistakes and to be corrected by other students. When the group fails to find the answer to a question or problem they ask the professor or assistants for help. While evaluating this new system our first conclusion is that perhaps it is not so impor& to discuss which fundamentals must be taught but, rather, the way in which we teach them. Our experience, which was basically a change in methodology with a minor revision in the contents, sup~ o r t this s conclusion. This new svstem reouires the nrofesr~ ~ Lor to be very efficient with respkct to th;time he devotes to each subject and simultaueously to judge how deeply to delve into each topic. We have obtained better results teaching models and subjects that students could use in the near future. We found that it is better to reduce the time devoted to lectures in favor of seminars for the reasons previously mentioned. ~
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Models and Molecules: A Laboratory-Based Course in Spectroscopy for the Nonscience Major T. C. Werner and L. A. Hull Union College Schenectady,NY 12308
Recently, the faculty a t Union designed a new General Education curriculum, requiring all students to take two courses in basic or applied science, one of which shall haw laboratories. This requirement has led to the development of several new laboratory-based courses in science for nonscience majors. Models and Molecules, a chemistry course for nonscience majors and the the subject of this paper, is an example of one of the new courses developed for this curriculum. Course Objective and Rationale The course objective is to introduce chemical ~ r i n c i ~ l e s to nonscience majors through the use of meas&ements with modem scientific equipment. We believe it is important to introduce these students not only to the way that chemists think but also to the types of tools that the chemist uses in the late 20th c e n t u 6 . h the process, we hope to demonstrate why these tools are required in modern chemistry. Finally, modem chemical instrumentation is increasingly expensive to obtain and maintain and can be more Presented at the Natonal Amencan Chemlca Soc~etyMeeung n San Franc sco (Apr 1992) as pan of the 'Sympos Lm on Teach ng Sclence wlth a Tecnno ogy Focus The New Ltoera Ans Program
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