Texts in Analytical Chemistry: An Uneasy Transition State Complex of Theory, Laboratory and Social Demands The practice of analytical chemistry has always heen responsive to the social needs of the times. Among the oldest surviving documents are descriptions of methods for testing for the "~ ienuineness of nrecious metals and other ~roducts. These emphasize the f&ction which analytical chemistry has alwavs had to fulfill: to orovide information of sufficientlv validnature, i.e., of the requisite statistical signif~cance,ahoui particular samples of material, so that meaningful decisions can be made about the material. Today, the question might be "Is the amount of mercury in the tuna above or below the limit which can he regarded as safe?" Textbooks in analytical chemistry have generally tried to mirror the needs and demands of society at large: this is es~eciallvapparent in respect to the types of samples for wliich the labbratory proredures are writkn and in the nature of the questions and problems usually included at the end of each chaptar. Thus, the ore, mineral &d metallurgical samples of the first half of the twentieth century have been replaced by samples more closely identified with immediate social concerns as experienced by the general public and as publicized in the media.,ex.. - . samnles . connected with ecolo~ical - and health problems. At the same time; startine durine World War 11, the changing practice of analytical-chernish in the .'red world", which has resulted from the continuine - develoument of an ever-increasing array of methods of separation and measurement with the concomitant increasing utilization of in~
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Philip J. Elving Uniuersity of Michigan Ann Arbor, Michigan, 48109 strumentation and automation, has strongly influenced the contents of analytical chemistry courses and texthooks, and has posed problems such as the proper balance between the basic principles of analysis and the discussion of specific glamorous techniques. The latter problem becomes particularly acute in the analytical chemistry laboratory. Functlon of Laboratory Instruction Courses in introductory quantitative analysis even into the early 1950's tended to stress laboratory instruction on the premise that the student was to be trained to develop into a skilled analyst; i t was a rare analytical course which did not include the complete analysis of a limestone and of a brass. Starting in the late 1940's and accelerating in the 1960's, the laboratory work became less and less focussed on the analysis of real samnles. and more and more on exneriments desiened to illustrate points in chemical theory. ~ n i n t e r e s t i rn e~ & d beean in the late 1960's with thecall bvstudents for relevance in the academic curriculum. There he& to he a return to real samples, although generally of different nature than those formerly used. Samples, which are frequently connected with environmental and ecological concerns, and with clinical aspects, were and are now being given students. One aspect of the analytical laboratory has been a major factor in textbook writing. Starting some time ago in the case of physical chemistry and, more recently, in that of organic chemistry, the lecture and laboratory were converted into
Volume 54. Number 5, M y 1977 1 269
- Morphology of Current Textbooks in Analytical ChsrnirtrF I... Elernentarv llnitial Courrel Level -
A. combiiea Type (class i e x t and Laboratory Manual) 1. chemistry Maior Oriented: Skaog-West (19761 2. Terminal Courre Type: Pietrzyk-Frank (19741 3. lnclu~ionin General Chemistry Courser: Swift-Butler (19721 B. Class Text$ peters-~ayer.Hlefje (1974) I . chemiitry ~ a j o oriented: r 2. ~ e t r n i n a Course l Type: Day-Underwood (1974) C. LabordtOrY Manualr: Harris-Kratochvil (19741 11. Advanced (Upper Clarr and Graduate1 Level A. Comprehensive Text: Laitinen-Harrlr (19751 6. ~ h y r i c a l(Instrumental) Methods of Analysis 1. combined ~ y p e (class Text and Laboratory Manual): willard-~erritt-Dean(19741 2. class Texts: Ewing (19751 3. Laboratory Manuals: Guilbaultt-Hawk (19701 C. Specialized Areal 1. Separations: Kalger-Snyder-HOrYath (19731 2. Measurement: Sawyer-Roberts (19741 3. ~lectronicsand Instrumentation: Malmrtadt-Enke (19i OTO economize on space, only a single text (generally recently publirhea and designated by author's name and year of publication) is cited ar an example of each catagory.
seoarate courses with the initial laboratom course often laeging by a term the initial lecture course, whkreas, in analytic$ chemistm, the combined course still nredominates a t least for the initiafcourse. This has given risk to the following dilemma. The Combined Text A major problem, which has confronted writers of textbooks in analytical chemistry, has been the inclusion in the same volume of a lecture or classroom text and of a laboratory manual. This anoroach has been an inheritance from the davs. " . just indicated; when the lecture portion of the course in quantitative analysis was largely a discussion of laboratory technique and an explication of the determinations to be made. As the scope of the material covered in the lecture increased, this approach was continued and the combined text-manual, eeuerallv with the laboratorv directions and procedures interspers&l at appropriate piaces in the text. persisted and is, inrleed,still common today, although, in recent years, a number of authors have separated text and manual into separate volumes, and texts have appeared without an accompanying laboratory manual; conversely, laboratory manuals have begun to appear which can be used independently of the particular classroom text used (see the table).
270 1 J o m l of Chemical Education
Contents and Organization of Analytical Texts As a consequence of the differences in (a) the type of student to whom the book is addressed, (b) the length and type of course for which the book is intended. (c) the extent of inclusion of physical methods of analysis, and (d) the personal predilections of the authors, introductory texts in analytical chemistry today are likely to reflect a much greater difference both in the identitv of the tonics covered and in the thoroughness of the treatment than do the introductory texts in the other areas of chemistry. The similarities and the differences between representative texts of the one-semester and two-semester tvDes currentlv popular and popular about twenty years ago s;e illustrative of the manner in which analvtical chemistrv has chanced in the past two decades. For example, while-the coverage of acid-base and redox titration has remained about the same, that of precipitation titration has slightly decreased and that of the use of complexation in titration has markedly increased; the latter reflects the introduction and popularization of methods using 1:l reactions involving such multidentate ligands as EDTA. The discussion of separation based on partition between phases has increased in a remarkable manner, mirrorine the extensive develooment of chromatomaohic techniques. Similarly, the increasing use in analysis o f l o ~ i c a l methods and electrical methods (lareelv based on oolaroeraphy, is reflected in the growth of their coverage. ' The discussims of eeneral lahoratorv"ooeratims have been . markedly curtailed. The disan~earanceof nrocedures for the svstematic analvsis of such materials as lim&one and brass reflects the shift in nractice of analvtical chemistrv as a result of the develooment bf more and more selective measurement methods bf the necessary sensitivity and precision. Some of the currently available introductory texts are clearlv intended to he used bv chemistrv maiors who will subsehuently take a course in physical methods of analysis. Consequently, tonics such as optical and electrical methods of anal& can betreated relatively briefly. On the other hand, some texts contain enough material to he used for a twosemester course sequence covering all of the topics which might be considered in undergraduate analytical chemistry. Some of the texts designed for courses to be taken by chemistry majors are claimed to be usable for one-semester terminal courses by a suitable selection of the material to be covered.
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