Symposium on the Beginning Course in Quantitative Analysis1
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INTRODUCTION PHILIP J. ELVING Purdue University, Lafayetie, Indiana
ATTHE PRESENT time there is widespread discussion both in industry and in academic circles regardmg the teaching of chemistry. The teaching of analytical chemistry is coming in for its fair share of criticism and comment, both complimentary and derogatory. The tremendous enlargement of the horizons of analytical chemistry during the past several decades is seen, for example, in the growth of microscale techniques, radiant energy absorption spectrometry, and the use of more and more apparatus of a complicated mechanical and electrical as well as optical nature. One of the courses in analytical chemistry which has recently come in for a great deal of searching attention is the first course in quantitative analysis. The importance of this course is stressed by the fact that it is taken by almost all students whose fields of study border on chemistry. In a large number of institutions the first course in quantitative analysis consists of only one semester of work and it is the only analytical course taken by those who are not majors in chemistry. For example, chemical engineers in most institutions now take only one semester of quantitative analysis. This is in contrast to former practice when the chemical engineers used to take from two to four semesters. This was a t a time when a chemical engineer could expect to do, when in industry, a fair amount of analytical chemistry himself. At the present time the average chemical engineer may do little or no analytical work once he is in industry. However, for the duration of his professional career he will almost always be concerned with the need for requesting and interpreting analytical data. In the case of the chemical engineer, a t least, the question is what type of material could be given h i m t o f i t h i for the latter task. The one-semester course in quantitative analysis given to nonmajors in chemistry is usually equally divided between gravimetric and titrirnetric work with, occasionally, an experiment in photometric measurement or pH determination. A number of questions are now being raised regardmg the contents of this course. Should the standard laboratory work as just mentioned be continued, or should more of the newer so-called instrumental techniques be included? If so, how much theory and how much practice concerning these techniques should or could be included? Further' Presented before the Division of Chemical Education at the 113th meeting of:the American Chemical Society in Chicago, April 19-23, 1948.
more, what types of apparatus should be used? Should one attempt to give the student a sampling of the whole variety of instruments that cover the electromagnetic spectrum from the viewpoint of radiant energy absorption or emission? Or a sampling of the various types of electrometric apparatus? In general, should the emphasis in the course in quantitative analysis be on laboratory practice or on the basic principles of analytical chemistry? How much material should be included on the analysis of organic substances? Up to the present, most of the exercises in the beginning course in quantitative analysis have been on inorganic samples, usually of a metallurgical nature, such as ores or rocks. The obvious reason is that such samples are stable and can be conveniently handled. Should the first course in quantitative analysis include an introduction to statistical methods? How much stress should be placed on a student's ability to do analytical calculations and solve problems? There are many who believe that the ability to solve problems indicates a fundamental understanding of the nature of the chemistry involved, as far as regards the analysis per se, and that the ability to do analytical calculations is basic to any attempt to interpret analytical data. In discussing the revision of the contents of the course in quantitative analysis it is in order to consider the economic factors involved in any major change in topics covered in the laboratory. The cost of many of the modern analytical instruments and gadgets is high; in fact, according to many teachers, prohibitively so for the average academic institution. Another factor that should be considered in any discussion of change in the topics covered is whether the background of the students in other technical subjects permits the elaboration or extension of the material now covered in the course. At the present time, the course in quantitative analysis is taken by students in either the first or second semester of their sophomore year. ' In many cases, physics is postponed for the students until their sophomore year, which means that they will have had one semester or less of physics when they begin the quantitative analysis course. This may have some influence on the amount of material on instrumental methods or methods involving applications of physical chemistry wh'ich can be absorbed. Fundamentally, what should the beginning course in quantitative analysis include in order to best train for
NOVEMBER, 1948
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This part will be concluded by a discussion of the their future technical work such groups of studknts as chemical engineers, home economics majors of diverse problems involved in teaching large groups of students interests, premedical students, and prospective research quantitative analysis. The tremendous increase in enrollment in academic institutions has caused many chemists? In the following symposium we shall try to answer problems, not the least of which are the problems insome of these questions, or, if not to answer them, a t volved in the teaching of large laboratory classes. least to discuss them and to indicate possible solutions The second part of the discussion will be devoted to a to the problem. consideration of the content and teaching of the beginIn the first part of the discussion, four authors will ning course in quantitative analysis by teachers of discuss what in their judgment should be covered in the quantitative analysis representing various types of incourse in quantitative analysis for training students in stitutions, such as large technical schools, small liberal their four respective fields of endeavor. They include arts colleges, and large state and private universities. a chemical engineer in a supervisory position, a repre- Each teacher will discuss the problem as i t is being sentative of a medical school, a supervisor of a field in dealt with in his type of institution. These latter inwhich home economics majors are. employed, and an ,dude the authors of some of the most popular textbooks industrial research director. on quantitative analysis used in this country.
