Chemical Education Today
Letters Reforming the General Chemistry Textbook
uncritically perceived as a sound introduction to four years of chemistry. Nonmajors who take this course are denied the chemistry they need, such as environmental and materials It was exhilarating to read your commentary on one prechemistry, but are forced to study things for which they have scription for launching “The Reformation” (J. Chem. Educ. no use such as calculations of ionic equilibria and the lan1997, 7 4, 484). I’ve voiced an opinion for some years now thanide contraction. that the macro-to-micro connection is a viable way to make The gridlock can be broken only by political action from chemistry intrinsically interesting to “clients” whose curricuthe highest level. ACS and/or IUPAC and/or AAAS and/or lum forces them to enroll in introductory chemistry courses. RIC could define a useful curriculum meeting Ron’s criteria. I advocate a top-down approach wherein, for example, a It probably would be widely considered and then adopted or printed circuit is examined initially as a macroscopic comadapted or disregarded—but not ignored, as are papers and posite “solid.” Then the solid would be examined with insymposia. Constructing such a curriculum would involve creasing magnification—the nature of the materials used to evaluation of all those contributions and would be an enorencapsulate the electronic components, the composition (and mous task, but until it is done there will be little change from fabrication) of the component parts such as silicon wafers the present unofficial but inviolable curriculum. for integrated circuits, etc.—until one can appreciate the Stephen J. Hawkes structure/bonding in silicon and the roll that impurities play Department of Chemistry in electronic conduction. Oregon State University Thanks for making the case for the macro-to-micro conCorvallis, OR 97331-4003 nection so convincingly.
[email protected] Edward T. Samulski Cary C. Boshamer Professor & Chair Department of Chemistry University of North Carolina Chapel Hill, NC 27599-3290
[email protected] *
* Dr. Gillespie’s viewpoint was expressed by one of the most revered writers in education thus: …theoretical ideas should always find important applications within the pupil’s curriculum. This is not an easy doctrine to apply, but a very hard one. It contains within itself the problem of keeping knowledge alive, of preventing it from becoming inert, which is the central problem of education. (Whitehead, A. N. Aims of Educatio ; Williams & Northgate: London 1932; p 7.)
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This is indeed a hard doctrine to apply. Much of what is taught in introductory chemistry has no application that is accessible to beginning students. Much of it attempts to deal quantitatively with concepts that are only qualitatively useful to most students, using simplistic algorithms that give dramatically incorrect answers. Topics such as hybridization are taught that have no physical reality and are useful only in sophisticated, obsolete calculations. The introductory chemistry curriculum is stabilized by feedback mechanisms that make change almost impossible. Teachers teach what is in the textbooks, textbook writers write what teachers teach. National exam writers examine what is taught and teachers teach what examined. It is further stabilized by the requirement of many non-chemistry programs that their students take the chemistry majors’ course because it is believed to be a “better” course, or is a more difficult course and separates students more firmly into admissible and nonadmissible. The standard curriculum, with all its errors and irrelevancies, is 10
I’ve just finished reading your article on textbook reform and, some details aside, I heartily agree with you. I teach both chemistry and mathematics at a private high school, and am fortunate to have in my classes, by and large, bright, motivated students. And some of them do, in fact, learn with understanding—especially those in honors chemistry, who encounter little difficulty with abstraction. More to the point, however, are those who, even in small classes with patient teachers, are overwhelmed and never really internalize the major ideas and the connections we teachers attempt to make for them. My reason for this note, however, is not to recount familiar woes, but to offer a suggestion, by way of analogy with the other discipline I teach. Mathematics teaching has undergone a major revolution in the past decade or so, largely as a result of the ready availability of graphing calculators. While this technology is not without its own drawbacks, much that was tedious (and now pointless?) has been eliminated and students have been freed to concentrate more on concepts. A notable example of a completely revised curriculum is the teaching of introductory calculus, using the text Calculu (John s Wiley & Sons, Inc.) produced by the Harvardbased Consortium led by Deborah Hughes-Hallett, et al. and funded by the NSF. The dozen or so authors, and many others, set out to teach calculus in such a fashion that students would have precisely the understanding that you speak of in your article, and not simply a grab-bag of tricks for finding derivatives and integrals. I don’t know the details of the process they used, but it seems to me that if you and others are interested in producing a chemistry text whose aims continued on page 26
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encompass both true “understanding” and an appreciation of the central role of chemistry, then it might be useful to talk to the authors of the consortium. Their text is now widely used at colleges around the country, as well as in high schools where calculus is taught. Admittedly, of course, the problems for a chemistry text will be different; calculus, by my count, contains two big ideas (indeed, for those with genuine mathematical gifts, these reduce to only one!), and it’s possible to spiral through them several times during the course. Chemistry, on the other hand, is far more complex, and presents agonizing problems when one tries to sort out what to include and what to omit. My own criteria are pretty much a matter of personal enthusiasm, although I take notice of the curriculum suggested by the advanced placement committee. Still, nomenclature and the systematic treatment of descriptive chemistry bore me to tears—and my solution is largely to ignore them; pH and buffers, however, provide a lovely opportunity to combine dynamic equilibrium, solution chemistry, stoichiometry, and even a bit of structure, and I spend 3 to 4 weeks on those topics. Clearly, a group starting at ground zero may have different thoughts on these topics as they come up with something like a coherent course. Universal agreement is surely an unattainable goal; the calculus course has caused a good deal of controversy among mathematicians, even while gaining a large following. (For example, the text contains no formal limit proofs and the mean value theorem is buried near the back of the book. But then the text is only 650 pages long; and, even in high school, with a non-honors group, it’s possible to cover, with understanding, most of the topics.) One more note on all of this. Whatever the decisions made about the text per se, it seems to me essential to have interesting and challenging problems. These should reinforce the ideas one is trying to get across (particularly the breadth of applicability of chemistry) as well as cause students to think. For some years, I’ve been using (in my honors course) Petrucci’s General Chemistry, partly for its clarity of presentation, but perhaps even more, for its superb problems. Stephen J. Fisher Lakeside School 14050 1st Avenue NE Seattle, WA 98125
[email protected] *
I couldn’t agree more with the commentary by Ron Gillespie, in the May issue of the Journal, that the standard Year I course and the standard textbooks have stagnated. I lecture in our smaller Year I course aimed at students who have done well in high school chemistry. Despite my attempts at enrichment, I am concerned that we are primarily just repeating the high school curriculum in Year I. In my course opinion questionnaire, students completing the course were asked to express in their own words what they saw as the principal purpose of the course. Responses varied, 26
but the most common was some variant of “a review of high school chemistry”. The top students enter university already having an understanding of the major Year I topics, and many are disappointed that there is so little challenge in Year I chemistry. Admittedly, many students go through high school chemistry at a low intellectual level and have not mastered basic concepts, so covering these is essential. However this needs to be done without losing the interest of the top students. A “theme” approach would allow essential high school topics to be covered again but in a new context. The Biological Sciences department at Brock University has been doing this for years. A major theme of their Year I course is neuroscience: totally new material, but to understand it many standard high school biology topics such as genetics must be included. The different context avoids the sense of “the same old thing, over again” and has apparently increased motivation and morale. Various themes are possible in Year I chemistry: for example, a materials approach, an environmental chemistry approach, a spectroscopic methods approach. The specific theme chosen is not too important as long as it is inherently interesting and gives students the sense that they are covering new ground. Once they have this sense, repetition of key material from high school should fit in naturally. A “theme” approach would automatically lead to a new kind of textbook. Maybe this is the route to take to achieve textbook reform. J. Stephen Hartman Department of Chemistry Brock University St. Catharines, Ontario L2S 3A1, Canada
[email protected] http://chemiris.labs.brocku.ca/~chemweb/faculty/hartman/
* Congratulations to Ron Gillespie for raising so many important points in his Commentary on the General Chemistry Textbook (1). I believe I addressed some of his concerns in my opening plenary lecture at the IUPAC International Conference on Chemical Education in Sao Paulo, Brazil in 1987 (2). The Proceedings of that meeting were not as widely available to the chem-ed public as I might have desired, so I hope I might have the opportunity of summarizing my views here. My introductory points were: Chemistry is not something that a student meets for the first time at high school or university. Chemistry is something which surrounds us everywhere, all the time. Chemistry, as the Chinese and Japanese symbols say so clearly, is the Study of Change, and chemical reactions should form the basis of elementary courses. The student should know “what happens” before facing the question “why does it happen?” However, far too many textbooks commence with topics like •
Atomic structure, isotopes, orbitals, and electronic configuration.
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• • • •
The Periodic Table, including trends in valence, ionization potentials, and atomic volumes. Calculations based on molar quantities. Bonding, electron pair repulsion theory, and molecular shapes. The nature of gases, liquids, and solids.
The introduction of theory too early can have a “turningoff ” effect on students. Development of theories, patterns, and generalizations in an introductory chemistry course should be conditional upon the following: (i) the students are familiar with the knowledge being ordered and (ii) the knowledge to be ordered is potentially useful and significant to the students. This is the essence of relevance. My major thesis followed—that courses could be made more interesting and more obviously relevant to the student if textbooks were to be rewritten with the topics regrouped into grand themes. Each grand theme should be introduced by a statement clearly illustrating why that particular theme is important in our lives. Each theme, and each topic within it, can be developed with a judicious mixture of observation (experiment or “outside” experience), description, and theory, in that order. Each theory can then be shown correctly to be what it is—a generalization based on the reactions and observations that precede it. Some of the grand themes that should be included in most introductory courses are shown in the following diagrams: Metals Our dependence on metals ↓ Metallic properties ↓ Reactions of the common metals ↓ Oxidation and reduction ↓ Electrochemistry → Batteries and electrolysis ↓ Reactivity of metals ↓ Corrosion ↓ Mineral resources ↓ Metal extraction ↓ Elementary structure ↓ Metals, non metals → ionic and covalent compounds ↓ Periodic System Carbon compounds Our dependence on carbon compounds ↓ Inorganic and organic carbon compounds ↓ Carbonates and bicarbonates ↓ Petroleum, natural gas and coal ↓ Hydrocarbons ↓ Functional groups → Reactions ↓ Solvents ↓
Carbon-based plastics and polymers ↓ Paints
(Carbon chemistry should be introduced early in introductory courses because it involves little or no theory at that level and deals with many substances that are familiar to everyone.) The Atmosphere Our dependence on the atmosphere ↓ The gases of the atmosphere ↓ Properties of the common gases ↓ The atmosphere as an industrial resource ↓ Air pollution Water Our dependence on water ↓ Water resources, water treatment, water pollution ↓ Properties of water → Intermolecular forces ↓ Solubility ↓ Surfactants, soaps and detergents ↓ Chemistry of water ↓ Chemical equilibrium ↓ Acids and bases ↓ Chemistry in solvents other than water Energy Our dependence on energy ↓ Sources and forms of energy ↓ Fossil fuels → Chemistry of the car engine ↓ Alternative fuels ↓ Foods as fuels ↓ Heat of reaction ↓ Energy in industry
This list is not intended to be exhaustive, but is sufficient to illustrate my major point. Such a structure facilitates the introduction of economic and social factors wherever they are relevant. I then presented suggestions for the fine detail of each topic under each grand theme together with the idea that such a structure can readily be adapted to both an elementary “Chemistry for the Citizen” course and a more detailed course intended to be the basis for the study of higherlevel chemistry. This contained too much material to be pre-
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Letters sented here, but the complete paper may be seen on our Web site: www.chem.uwa.edu.au/academics/arhcole/chemed.html. Literature Cited 1. Gillespie, R. J. J. Chem. Educ. 1997, 74, 484. 2. Cole, A. R. H. Proceedings of the 9th ICCE, Sao Paulo, Brazil, 1987; pp 39–57. A. R. H. Cole Department of Chemistry The University of Western Australia Nedlands WA 6907 Australia
[email protected] * Ronald Gillespie in his commentary “Reforming the General Chemistry Textbook” (May 1997, p 484) again reminds us of the many discussions but little action toward changing the textbook basis for our largest chemistry course for science majors. He asks the question—“Who will initiate and support reform?” He, apparently unknowingly, answers that question when he suggests that only groups such as the American Chemical Society (ACS) or the National Science Foundation (NSF) can provide the initiative to make major changes. Following its pioneering traditions with ChemCom (Chemistry in the Community) and CIC (Chemistry in Context), the ACS has embarked upon a major curriculum project for the science major’s general chemistry course. This project, currently referred to as Chemistry in a Biological Context (CBC), is a joint venture between the ACS and W. H. Freeman Co. As Gillespie urges, the textbook will focus on “the macroscopic world of observations and the microscopic world of atoms and molecules”, built principally upon biochemical concepts. The content will provide an interesting and relevant context upon which students will build their knowledge of chemistry. Though still in its early stages of development, CBC will be a very different curriculum from the traditional approach that most institutions now use. And, consistent with Gillespie’s suggestions, CBC will be a total firstyear curriculum package including laboratory and mechanisms for faculty development. The ACS is proud of its record of innovative curriculum development. We have no doubts that CBC will lead a revolution in general chemistry teaching and learning. Stanley Pine Chair, ACS Society Committee on Education Department of Chemistry California State University, Los Angeles 5151 State University Drive Los Angeles, CA 90032
[email protected] Ronald Archer Chair, Chemistry in a Biological Context Advisory Board Department of Chemistry University of Massachusetts Amherst, MA 01003
[email protected] 28
Herbert Kaesz Chair, Chemistry in a Biological Context Editorial/Writing Team Department of Chemistry UCLA Los Angeles, CA 90095-1569
[email protected] * Ronald Gillespie’s commentary in the May 1997 issue of this Journal struck a chord (indeed many chords) with me. The pace of reform in chemical education is indeed painfully slow, and mainstream textbooks are often well-written, beautifully produced reiterations of the tell them everything we ever want them to know philosophy of teaching introductory chemistry. But to say that “publishers are unwilling to invest in unconventional books” is incorrect. There are a number of publisher-supported efforts to produce textbooks and textbook alternatives that address many of the issues raised by Dr. Gillespie. We are currently using the second edition of The Chemical World, by Moore, Stanitski, Wood, and Kotz, from Saunders Publishing Co. According to the preface, the text is designed to “cover the truly important concepts of chemistry” and to emphasize conceptual understanding and problem solving. The book is shorter and less expensive than a typical general chemistry text. Topics from the Nernst Equation to Molecular Orbital Theory have been axed, and much more emphasis is placed on relating “the macroscopic world of observations to the microscopic world of atoms and molecules”. In the new edition, a major emphasis has been the integration of organic and biochemical concepts into “general chemistry” topics such as thermodynamics. This is not to say that The Chemical World is the definitive “truly new text” sought by Professor Gillespie. Other initiatives that address these issues will be very welcome. What I question is whether the government or private industry should fund these efforts. In my judgment, the real paradigm shift in chemical education requires a de-emphasis of the textbook and a new emphasis on other learning tools, including instructional technology. To provide our students with a “picture” of submicroscopic behavior, we need animations that use our best representations of what molecules look like and how they change as they interact with other molecules. To convey our macroscopic world we need high-quality videos complete with sound. I think it would be better for the NSF to fund the creation and distribution of unrestricted, high-quality videos, animations, and other media forms. Right now these materials are scattered in a myriad of locations and media formats and ensnared in a copyright hall of mirrors. Putting free, high-quality media in the hands of chemical educators would be a much better way for the government to catalyze paradigm change. Jimmy Reeves Department of Chemistry University of North Carolina at Wilmington 601 South College Road Wilmington, NC 28403-3297
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Letters Regarding the recent commentary “Reforming the General Chemistry Textbook” by Ronald Gillespie, I agree with Gillespie in this matter. I am a physicist who teaches firstyear chemistry at Maranatha Baptist Bible College. General chemistry textbooks make the same mistake that general physics textbooks make. They cover too much material. The problems emphasize applied mathematics while minimizing the understanding of the concepts. I would like to see a chemistry textbook developed in a manner similar to Conceptual Physics by Paul Hewitt (7th edition, Harper Collins College Publishers, 1993, ISBN 0673-52185-0). Hewitt develops physics understanding with very little mathematics. I would like to see similar textbooks developed for chemistry. The problems in Hewitt’s book emphasize everyday applications of physics; therefore the students get more involved with the course. Robert Hill Science Professor Maranatha Baptist Bible College 745 West Main Street Watertown, WI 53094 414-261-9300, ext. 352
[email protected] * Professor Gillespie, in his Commentary “Reforming the General Chemistry Textbook”, asks “Who will initiate and support reform?” He suggests that “Getting such books published and adopted will need some initiative from bodies such as the National Science Foundation...” and that “Their support and financial assistance will be required not only to subsidize the writing and publication of such books, but also for retraining workshops for instructors.” We are pleased to report one such effort underway through the National Science Foundation’s Systemic Changes in the Undergraduate Chemistry Curriculum initiative. The ChemLinks Coalition and ModularCHEM Consortium are collaborating to produce a new approach for the first two years of the chemistry curriculum. Topical modules, based on questions relevant to students, develop the chemical principles needed to answer those questions on a “need-to-know” basis and, in the process, model the way chemistry is actu-
ally done. Active and collaborative work in classroom, laboratory, multimedia, and homework materials changes significantly the nature of the text and the way students use it. With modules that permit the instructor to adapt materials to meet course goals by choosing explorations of differing depth, we intend that all students benefit from the scientific literacy provided by showing the connections between chemistry and other sciences, technology, life processes, and the physical world. By involving a large group of module authors from 2-year and 4-year colleges and comprehensive and research universities in developing and testing these materials, we expect them to be adaptable to a wide range of institutional settings. With John Wiley and Sons, we are currently producing a draft edition of modules for testing within the two consortia, which will be followed a year later by a beta-test version for testing in some additional schools. A first edition is planned for general use in the year 2000-01. Integral to the NSF project and the publisher’s plans are workshops for those who wish to use this approach. NSF has also set aside Course and Curriculum Development support for individual schools or consortia wishing to “adapt and adopt” this approach. For further information about this project consult our Web sites (http://chemlinks.beloit.edu, http://mc2.cchem.berkeley.edu, http://www.ehr.nsf.gov/EHR/DUE/programs/ccd/cheminit.htm). Brock Spencer ChemLinks PI Department of Chemistry Beloit College Beloit, WI 53511
[email protected] C. Bradley Moore ModularCHEM PI Department of Chemistry University of California Berkeley, CA 94720
[email protected] Nedah Rose Executive Editor, College Division John Wiley & Sons, Inc. 605 Third Avenue New York, NY 10158
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Letters The author replies: It was encouraging to receive many notes and letters of support for the thoughts expressed in my Commentary “Reforming the General Chemistry Textbook”. I was also pleased to learn that there are two projects underway that are attempting some serious reform and I look forward to seeing what these projects produce. It is good to see that the Chemistry in a Biological Context (CBC) approach is following up on the ChemCom and Chemistry in Context new curricula. I appreciate the appeal of the biological approach, but in my opinion this is not the easiest way to introduce students to chemistry. It will give students a rather one-sided view of chemistry and its applications, it will not appeal to all students, and many instructors will feel that they do not have enough background to be able to teach it well. There have been experiments with a materials science approach (1) and Hartmann mentions other possibilities such as an environmental approach. But all these single theme approaches suffer from the disadvantages that I have mentioned. I also appreciate the appeal of the modular approach, which certainly gives instructors considerable freedom in developing their own individual courses. But, unlike authors of a single comprehensive text, authors writing a particular module do not have to fit into an overall logical development of the subject from the beginning. Moreover, authors writing on a single topic that they know well are tempted to go into too great a depth and in too much detail. A course made up of modules will probably suffer from an excess of material and detail as is the case with many of the present overlong comprehensive texts. My preference is to give students a broad view of chemistry that enables them to appreciate the fundamental ideas of chemistry (2), to understand what chemists do—synthesis, analysis, and the determination of structure, for example—and to appreciate the importance of chemistry to an understanding of other sciences, such as biochemistry, materials science, geology, and environmental science. In this way students will have a broad enough background in chemistry to see that chemistry is very relevant to their own future interests, whether this be as specialists in medicine, biology, engineering or physics, for example, or simply as citizens in a society increasingly dominated by science and technology. My own text (2) was a step in this direction but was restrained from being as revolutionary as I would have liked by the publisher and the reviewers. I agree wholeheartedly with almost all the opinions expressed by the respondents to my article although I am distressed to learn that descriptive chemistry drives Fisher to tears. Perhaps Fisher finds it a bore because he teaches it using the conventional general chemistry textbook treatment that runs through the groups of the periodic table, usually at the very end of the book. But it does not need to be taught in this conventional way and it does not need to be boring. Theories and principles have been developed over the years to rationalize and explain the facts of inorganic and organic chemistry. Before teaching them we should first describe, (better still demonstrate), and discuss in an organized and rational way the basic facts (observations) on which they are based. In other words inorganic chemistry, and for that matter organic chemistry as well, should be fully integrated into the course and not presented as separate subjects. My method has been to present a few related facts, for example some simple chemistry of the halogens, on which some theory can be based and then some more facts, for example some basic chemistry of phosphorus and sulfur, two more elements that are important in many contexts, to enable some more theory to be presented and illustrated and so on (2). Perhaps my own text placed too much emphasis on inorganic chemistry and it would be good to see more of the observations of organic chemistry, in particular, and biochemistry and materials science as well, used to introduce and illustrate some of the principles and theories. Nomenclature is certainly boring and 32
of no great interest to most chemists who need to know what is necessary to publish their results but who do not otherwise often use it. My approach is to introduce only what is absolutely necessary and only when it is required. Reeves suggests that the text book should be de-emphasized and a new emphasis placed on newer learning tools. While I agree that we should make as much use as possible of the new teaching and learning techniques, it is of no value to teach the wrong material even in the best possible way. New curricula and new textbooks are still needed to define a new course or courses. Contrary to Reeves I also still believe that publishers are generally reluctant to invest in unconventional books for several reasons. They are understandably mainly interested in making money or at least not losing money and today’s very competitive market is not conducive to taking financial risks. Moreover, it is very difficult for publishers to judge the potential of an unconventional book. A well-written, well-organized, student friendly, conventional book is fairly certain to have reasonable sales but it does nothing to contribute to the improvement of the general chemistry course. There have, I agree, been a few attempts to move text books away from the conventional approach. Examples are The Chemical World (3) and my own text (2) but they have been rather cautious attempts and not revolutionary enough to bring about the real change that is needed. It is interesting to note that the two major efforts to bring about reform that were mentioned in the letters are supported and subsidized by the ACS and the NSF. Indeed, as Hawkes very forcefully and clearly points out, without such support change is impossible. Underlying all these problems is the fact that far too little science including chemistry is taught in the years before the high school chemistry course. So students are very poorly prepared for the too theoretical and abstract material that is often presented in the high school preuniversity course. I do not feel competent to comment on the teaching of science in the earlier school years, but given the present situation it seems to me that for the majority of students the present conventional high school course is inappropriate. I do not know how widely the ChemCom approach has been adopted but I do not think that there will be a big change in high-school chemistry until the collegeuniversity general chemistry course is reformed. The urgent priority is the reform of the general chemistry course. Chemistry is a complicated and ever growing science. Formulating a new curriculum that will give students an enjoyable, interesting, useful, and relevant introduction to modern chemistry, that will make its fundamental ideas and concepts understandable at this level, that will give students an appreciation of the chemists particular atomic and molecular view of the material world and prepare them to be chemically literate citizens is a challenging and formidable task. But it is one that for the future of our subject and for the future generation of the students and the citizens of tomorrow we must undertake. Literature Cited 1. Ellis, A. B.; Geselbracht, M. J.; Johnson, B. J.; Lisensky, G. C.; Robinson, W. R. Teaching General Chemistry: A Materials Science Companion; ACS Books: Washington, DC, 1993. 2. Gillespie, R. J.; Eaton, D. R.; Humphreys, D. A.; Robinson, E. A. Atoms, Molecules and Reactions: An Introduction to Chemistry, Prentice-Hall: Englewood Cliffs, NJ, 1994. 3. Moore, J. W.; Stanitski, C. L.; Wood, J. L.; Kotz, J. C.; Joesten, M. D. The Chemical World: Concepts and Applications, 2nd ed., Saunders: Philadelphia, 1997.
R. J. Gillespie Department of Chemistry McMaster University Hamilton, ON L8S 4M1 Canada email:
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