Time to retire - American Chemical Society

unsatisfactory concepts still used in our teaching are here- with proposed for ... If we, as teachers, could agree on at least a few of these items, w...
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TIME to RETIRE* GRAHAM COOK Albrigbt College, Reading, Pennsylvania

Of the various methods of fixation of nitrogen usually studied in an introductory course, it is the most spectacular, and certainly the easiest to teach. The students like it because it involves the fewest equations, all of them simple and "easy to balance." The process is not only spectacular, but easily demonstrable. Evidence for its popularity among teachers is offered by the appearance in recent years of a number of excellent NE of the major problems that always confronts papers which describe lecture demonstrations of it.= us as chemistry teachers is the rapidity of the Because of our liking for it, and the consequent emchanges in the science as we teach it. We have to phasis placed upon it, the student gets the idea that it modernize our courses continually, not just occasionally. is the most important method for the fixation of nitroWe have to keep abreast of the times. There are oc- gen. Even if he doesn't get this idea, he will acquire a casions, of course, when this need for modernization is conception of it which is all out of proportion to its real particularly stressed, as, for example,at the "Symposium importance. For despite the fact that on paper or for Modernizing the Course in General ChemistrY" of blackboard or lecture demonstration table it looks like a the Division of Chemical Education a t the eighty-eighth good process, i t is of no commercial significance whatmeeting of the Society a t Cleveland in 1934. From ever today. At no time has it attained the importance the contributions to that symposium, and others pub- that we teachers have given it. There has been only lished from time to time, we receive the necessary stim- one plant that has successfully produced nitric acid by ulus to keep our courses modem. the arc process, and that is a plant in Norway. The AU of these changes involve the addition of a lot of maximum production of this plant was 45,000 tons in material, so much so that someone has aptly said that 1915. There were a few other plants, but these, for our courses suffer from "additionitis." We seem to be all practical purposes, never got beyond the experipretty well agreed on the fact that additions should be mental stage. Today these plants have all been made, and partially agreed on what we should add. But changed to produce fixed nitrogen by the ammonia procwe fail, perhaps, to get together on what we shouldleave ess. The method is considered obsolete today.3 I proout. After all, we cannot add indefinitely to the con- pose, therefore, that we retire this process to the histent of our courses, especially the introductory courses tories of chemistry, where it properly belongs. in general chemistry. In the procedure of modernizaAnother time-honored process that I would relegate tion, some things are automatically eliminated. But to limbo, or a t least to those same histories of chemisnot all of them are. There are many concepts and proc- try, is the LeBlanc process for the manufacture of soda esses which we teach today that could be safely dropped. ash. This appears to be another process from which we It is time to retire them. If we, as teachers, could hate to part. In several texts today the method is agree on a t least a few of these items, we could then given as much space as the present-day Solvay process, make room for some of the new things. It is not the although it is pointed out that the method is obsolete. purpose of this paper to list everything that should be It is still included in some syllabi. This indicates that retired, but to propose only a few of the more obviously we are still teaching the LeBlanc process, for if we as outmoded processes and unsatisfactory concepts. No teachers didn't want to teach it, it would quickly disdoubt they will suggest others. appear from the texts. Suppose we agree to retire it. The first topic that I would urge for elimination from It has never been used a t all in this country, and where the general chemistry course is the arc process for the it has been used it is now obsolete. According to one fixation of nitrogen, the so-called Birkeland-Eyde proc- authority,' "LeBlanc's process for soda ash manufacess. This apparently is an industrial process that ture has now disappeared. . . . .[it has] sunk into oblivmany of us like to teach. It appears in a number of ion." But i t hasn't done so in our high-school and texts and syllabi, even in recent revisions.'

As the science of chemistry progresses, new material is constantly added, but there is an afiarent reluctance to discard any old material. Several outmoded processes and unsatisfactory concepts still used i n our teaching are herewith proposed for discard.

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* This paper was presented in part at a meeting of the Lehigh

Valley Section of the American Chemical Society, February 19,

ZITPFANTI. "Demon~tratin~ - the fixation of nitroaen." ibid.. 9

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