To the Editor: To the Editor: To the Editor:

G. M. Bateman, Arizona State College ... L. R. Dswson, bniversity of Kentucky ... College. Education. H. S. Hemehway, Simmons College. H. L. Hunter, C...
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J. A. Schufle, New Mexico School of Mines H. A. Smith, Milton (Mass.) High School M. C. Sneed, University of Minnesota B. D. Van Evera, George Washington University E. C. Weaver, Phillips Academy

To the Editor:

To the Editor: The group whose names appear below believe that a generally recognized term ig needed, particularly in the teaching of general chemistry, for the quantity of matter which is one gram divided by Avogadro's number. Many names have been proposed for atomic mass units (atun, atwu, dalton, hep, microcrith, pel, pip, plunket, xyzt). Some of these are used a t present in a limited manner, but non'e has become generally popular. Since the quantity everyone has in mind is one gram divided by Avogadro's number, the undersigned urge the adoption of the term AVOGRAM, because this hints a t the relationship and is easily pronounced in classroom discussions. The student can also he given the derivation of the term from the words Avogadro, oxygen, and gram, and the reasons for the importance of these. The adoption of this term will in no way limit or hinder those who l i e to use relative atomic weights in the teaching of general chemistry. However, many of us believe that the average chemistry student learns more clearly when he has a unit of atomic and molecular mass to use, particularly when he is attempting to thiik about the mass of single atoms or molecules. We believe that a sodium atom with a mass of 23 avograms perhaps means more to these students than a sodium atom with a relative atomic weight of 23. For those who like to use a named atomic unit of mass in teaching atomic and molecular weights the undersigned urge the general adoption of the term AVOGRAM. G. M. Bateman, Arizona State College H. S. Booth, Western Reserve University P. W. Boutwell Beloit College H. T. Briscoe, fndiana University V. R. Damerell Western Reserve University L. R. Dswson, bniversity of Kentucky A. L. Elder, Syracuse University H. E. Everson, University of Cincinnati E. L. Grove. St. Cloud Teacher's Colleee H. S. Hemehway, Simmons College H. L. Hunter, Clemon College K. E. Jackson, Universit of Alabama C. R. Keizer Central Co%ege W. G. ~ e s s e iIndiana , State Teacher's College R. Meinhold, Rhode Island College of Education W. C. Oelke, Grinnel College J. V. Quagliano, University of Notre Dame D. L. Rrtndgl, Albion College H. H. Rowle , University of Oklahoma R. I. Rush, 6entre College E. P. Schcch, University of Texas

May we express our appreciation for your editorial in the October number of the JOURNAL OF CHEMICAL EDUCATION.We agree that the theory of acids and bases should not be extended to include oxidizing and reducihg agents, and we should like to add the following comment to your editorial. The theory can be broadened to include electronpair donors and acceptors without departing from the typical experimental behavior of acids and bases. But oxidizing and reducing agents cannot be included without abandoning the attempt to make the theory fit the facts. Lewis stated this and we have emphasized it in our book. Although it is true that certain substances which we think of as primarily acids can sometimes behave as oxidizing agents, and vice versa, yet the experimental criteria for recognizing the difference between the two kinds of reactions are entirely different. Furthermore the theoretical explanation is clear cut. Acid-base reactions involve the sharing of electron-pairs. Oxidation-reduction reactions involve the outright transfer of individual electrons. Relative to your question regarding the size of the "pile," we believe that the answer is determined by the criteria of chemical behavior. A thoughtful survey of chemical reactions indicates three large and distinct piles based on electronic interpretations of their reaction mechanisms. In addition to the two piles already mentioned, acid-base and oxidation-reduction, there is the pile of odd-electron molecule (free radical) reactions where a covalent bond results from the interaction of two molecules each having an odd (unpaired) electron, or the reverse case where such molecules are produced through the splitting of a normal covalent bond.

To the Editor: Writer Standen's explanation of "Three Ways of Teaching Chemistry" seems to require a brief correction since, in quoting my 1945 paper, he completely overlooked or ignored the cardinal point in that paper and all of its sequels--concerning intellectual honesty about atomic theory. It does not seem to matter much whether a science course is taught "inside-to-outside," "outside-to-inside," upside-down, 0.r sideways: if we are not teaching the known truths, the whole effort-in plain American appraisal-is "cockeyed." It is not the poor teachimg psychology that I fear, (Continued a page I 17)

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