provocative opinion Chemistry Service Courses Dispense with the Lab? John F. Wojcik Villanova University. Villanova, PA 19085
Chemistry departments often offer several service courses for other departments. In universities offering nursing and engineeringdegrees as well as core science co&es fornonscience majors, this service may be considerable. The content of these courses is sometimes a matter of contention, the served knowing what they want and the servers knowing what should be wanted. The importance of the laboratory session that ordinarily is associated with first-level courses is being brought into question. Often a solution to a scheduling problem is simply the dropping of the laboratory requirement. This has been facilitated by the compartmentalized approach t o education that exists in most colleges and universities. The lecture part of the course becomes separated from the laboratory part with separate course numbers and separate grades. Of course, if enrollments are large, this aids scheduling. However, i t also leads to specious reasoning. "The lecture course and laboratorv course are inde~endentcourses. Indeoendent courses are such that onemay be taken without' the other. Therefore. one mav take the lecture course without taking the laborkory coukae." At the root of the problem is the equivocal use of the word "independent", a use sanctioned by practice. I t seems to have become a principle of college education that courses which are numerically independent are therefore inherently independent!' In what follows, 1hope to show that significant laboratory experience should be part of first-level chemistry courses, not hecause they are "fun" (they may be so, but basketball and the camDus cinema mav be more so). not because thev teach prtnciples (this is a very inefficient way to teach pr~nciples), and not because thev develoo techntcal skills (electrical engineers need not become skhful in titration); but because the very nature of the subject matter demands it. Quite simply, it is pedagogically and philosophically unsound to teach chemistry without laboratory experience.
' Of course, the extreme of illogical reasoning is used here.
A gccd account of the nature of modern science in the context of its historical development can be found in Jaki, Stanley L. The Rele vance of Phvsics: Universitv of Chicaao: Chicano. 1966. 'Mathematics IS taken here in a very broad sense and includes. In additlon to the expected algebra and caicu JS. geometly. dtscrete mathematical structures. symbohc logic, mdeed any axlomatc system of symbol manipulation. That chemistry, like all of the physical sciences, is a malhematicized viewing of nature does not imply that to bea oracticing chemist one must coistantiy and consciously use matheniatics. TGsubject matter of chemistw has room for the svnthetic chemist who never consciously adveis to the matnematiCs as we1 as the ihyslcal chemrst who only adverts to the mathematics. here we are taking of Lnaer ying logc rather than practice.
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In order to see the proper place of the laboratory experience, it is necessary to reflect a bit on the nature of modern physical s ~ i e n c eI. ~ t is safe to state that modern physical science, chemistry included, is a mathematicized account of material nature. Of course. the material world is an essential ~ ~ part of modern chemist&. I t is what chemists study! The reactions, the colors, the smells (where permitted), the odd pieces of glassware and exotic instrumentation, all of this is what makes the chemist feel a t home. Nonetheless, starting with Galileo and Descartes, physical science has couched all of its explanations and internretations of phvsical realitv in terms of quantitative relationships and geo&trical s t k c tures. And so, the mathematics of chemistry is not merely a painful adjunct to aid the chemist. It is the soul of the science, and, if this soul were to depart, one would be left with a body of colorful facts, interesting and perhaps entertaining, hut not scientific. While mathematics3 is the soul of physicalscience, mathematics also lives a life of its own. Mathematics has no need for material nature (except to the extent that ntathematicians are material). The objects it studies have no need to he constructed. How does one study a function in the lahoratory anyway? A baskethall may help me know what asphere is. hut the mathematician can talk about spheres and draw all sorts of conclusionsahout them and never construct a single material sphere. The uhjects that the mathematician manipulates exist only in the mind and have no need of matter. If one doubts this, consider the geometrical figures of nonEuclidean geometry. How does one construct n triangle such that the angles do not add up to 180°? T o say that mathematics is applied to chemistry is an oversimplification. It is more accurate to state that the mathematical objects are created in their own realm and then are "infused" into the material reality that the chemist is studying. Take hydrogen as an example. Starting with quantitatively expressible properties, the material, flammable, buoyant gas is transformed into a pair of points located a certain number of angstroms from each other that move according to certain mathematical laws. We so mathematicize the hydrogen that we no longer say that it heha\.es accordina to the mathematical l a w of anharmonic motion: we say &at it is an anharmonic oscillator. The description becomes inseparable from the thing.4 We now have opportunity for an interesting reversal. The points, lines, and functions of mathematics have been used t o create a picture of the reality underlying our chemical experiments. In the process new mathematical objects are created. For exam~le.a collection of ~ o i n t sarraneed in a definite geometric&fa$hionand having additional ;umbers associated with each ~ o i n (derived t from the masses of the points) is created to represent a molecule, an object having a ~
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material existence. Now comes the reversal. This collection of geometric points, having its origin in the material world, can now return to the mathematical world and live a life of its own. In spite of the intimate relation between the physical objects to be described and the mathematical descriptions, the mathematical descriptions can become mathematical objects to be studied independently of any connection with the experimental world. Some examples of this can easily be given. Consider first what is often called Lewis "dot" structures. I t is suggested that one list the rules for creating these structures and then modify the rules such that the words "electrons", "atoms", and "molecules" are replaced by the words "dots", "squares", and "structures" with the different kinds of atoms being replaced by squares of different colors. One is then told to construct structures using the listed rules. Of course, the structures are now purely abstract objects, mathematical objects. Anyone not possessing any knowledge of chemistry can construct these structures with rules in hand. Only the chemist who knows the concordance between the two languages can check the answer to see that the nonchemist, given the definitions and rules, can construct valid Lewis structures. In a similar fashion, a four-year-old can be presented with a box of colored balls with holes in them and sticks and then told to build "things" from them, TinkerToy fashion. Given that the set of balls and sticks came from a molecular modeling kit, any chemist will immediately recognize the representation of valid molecular structures. At a more sophisticated level, one can give the Schroedinger equation for the anharmonic oscillator to a mathematician who, in turn, will generate eigenfunctions with no need
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whatever to know about infrared spectroscopy or molecules. Herein lies a great danger in the study of chemistry. Because of the presence of mathematics in the very core of chemical explanation, and because of the ease with which this mathematics can dissociate itself from the material world in which it is grounded and enter a purely mathematical realm, i t is quite possible, perhaps inevitable, that a chemistry course taught without laboratory experience will become solely a course in mathematics and abstract symbol manipulation. Since chemistry, like all of the physical sciences, is a study of the material world and is concerned with tangible, contingent, and transient objects, an abstract study of its symbols with no experiential reference to material reality is worse than one-sided, i t is a complete distortion of a particular knowledge of reality and has no place in a college or university curriculum. I t should be clear that the laboratory experience is not merely an entertaining, reinforcing, or training experience. It is not a way of providing employment for faculty or teaching assistants. I t is an essential experience, a part of the process by which the intellect comes to "see" what the science of chemistry is. A place for the laboratory experience in the curriculum is demanded by the verynature of the chemical science. T o teach chemistry, and in particular, first-level chemistry, without the laboratory experience is equivalent to teaching about music from textbooks without ever listening to an actual composition. Perhaps accrediting agencies and deans and all others charged with forming professional curricula will see that giving in t o professional constraints without regard for the demands of the human intellect will, in the long run, do more harm than good.
