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a good overview of the power of this tool of analytical chem- istry. The pervasive use of analytical ... year colleges or vocational schools. The cour...
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Analytical Chemistry-or "I Wonder What I've Really Got in Here"

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E V- -~ N so -~ often. the sueeestion is made that analvtical chemistry is not really a sub-discipline of chemistry at all but merelv a tool (albeit a widelv used one) to assist the practitione; of the other sub-disciplines in "real" chemicaiinvestigations. Closer examination of the workings of analytical chemistry, however, reveals a unity in the application of a formal, logical approach to diverse problems that can all he informally summed up by the question in the title above. All analytical techniques, from introductory "wet-lab" qua1 to advanced spectroscopic investigations, are based on the idea of the ordered and logical eliminations of alternatives until (one hopes) the sole possibility remains. Sometimes finding the answer involves several successive and diverse techniques, and sometimes (as within the oual scheme) i t is the result of carefully repeated procedures in a long, elegantly designed network. Whatever the approach, the formal application of the tenets of logic to find out "what (or how much) do I have here?" mark the process as analytical chemistry and set it aside from other investigative techniques. Indeed, the very fact that qualitative analysis is usually the student's first introduction to using logic in a formal and structured way has made it as valuable as a curricular tool as it is as an analytical technique. The first step in analyzing an unknown substance often is to separate it into its various components and then to investieate them individually. Chromatography was one of the first oithe modern separation techniques to he developed and is used not only in analysis but also to separate reaction products so that particular components may be used in further reaction steps. Part I of a review article on "Separation Technology" bv Mickev- (. ~ a e e997) covers the development of and the many different types i f chromatography available and offers a eood overview of the power of this tool of analytical chemistry. The pervasive use of analytical techniques such as chromatography has led to a diversity of approaches to teaching them, each tailored to the way in which the technique will he applied. Leonard (page 1022) has included several of the classical analytical separation techniques in his course which is described as "A Practical Introduction to Separation and Purification Techniques for the Beginning Organic Chemistry Laboratory." In two more specific examples of applications of analytical techniques, Williams (page 1003) presents his undereraduate organic laboratory ex~erimentwhich uses H P L ~ detect I ~ small amounts ocanthracene in trlptycene, and Akers (pare lo1 l ) offers a question on the use of hufters in electrophbr&is in Exam ~ u e i t i o nExchange. The development of analytical techniques involving complicated (and expensive) instruments has led many teachers to turn to another instrument-the computer-to teach the principles of a procedure through simulation. Two such simulations are described in this month's Computer Series'Bits and Pieces. Suelter, Morris, and Hill (page 988) found that the sophisticated instrumentation available for scintillation snectrometrv allowed operators to learn how to use the equipment without understanding the principles behind it, so they designed a simulation which would introduce the