What's the use

New Rochelle HS. New Rochelle. NY 10801. The Electronic Perlodlc Chatl ot the Elements. TO the Editoc. A recent article proposed a new periodic table ...
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By using this method, we can name and symbolize the elements with a maximum of two letters, and we will preserve the numerical value. What do you and your readers think? Joseph Sencen New Rochelle HS New Rochelle. NY 1 0 8 0 1

many authors continue to fuel this enterprise by devising new schemes (11-13). A eood oeriodic tahleshould hiphlipht. above all else; chemical trends and similarities. ~ n s G a d , t h e o r o ~ o s e dtable reinforces the concept of electronic configucatibns and implies that it represents the foundation-of chemistry. This is misleading, but of course I do not deny the usefulness of electronic configurations as an approximation. T o conclude, why should we as chemists buy this version Literature Clted Marttans Osorio. H.; Goldschmidt, A. J. Chem. Educ. 1989,66,758. 2. P i l m F. L.J. Chem. Edur. 1978.55, 2. 3. Smrri. E. R.Educ. Chem. 1389.26.3. 1.

The Electronic Perlodlc Chatl ot the Elements TO the Editoc

A recent article proposed a new periodic table that avoids the usual relegation of the f block to the foot of table ( 1 ) . There are a number of objections that I would like to raise against this proposal, concerning both specific points and 1 more eeneral issues of chemical education. Firstly, . Figure . by the authors does not in fact refer to orbital as energies but to the order of filling of orbitals (2.3). The authors seem to be unaware of the fact that other periodic tahles have been proposed that share this feature of incorporating the rare earths into the main hody of the periodic table, which they seem to value so much. A casual insoection of the excellent comoilation of oeriodic tables bv Mazurs would show numerous such cases i4). The nrooosed version seems to blur the traditional moueing of elements according to similar chemical prqperties. Even if we consider diaeonal downward lines in search of the familiar groupings, we find sequences such as 0,S, Cu, Se, Ae. and T e that clearlv introduce serious anomalies. The aithors themselves seem to be completely unconcerned with the chemical aspects of their proposed table, and their work is merely a tedibus exercise & writing electronic configurations. The fact that as manvas 10 separate points are needed t o describe the layout of-this tabie wouid seem to argue against its adoption. As a recent article in this Journal has convincingly argued, the element lutetium should be grouped together with scandium and yttrium as marking the beginning of the transition series. Incidentally, this feature emerges from considerations of electronic configuration as well as chemical ones (5).I t is very difficult to discern any relationship between these three elements in the proposed new table. Turning t o more general issues now, i t has often been nointed out that the periodic table is not explained bv electronic configurations, any more than chemistry is explained bv. auantum mechanics (6. 7). The implied reduction of . chemical behavior to electr&c configura;ions of atoms does the studv of chemistrv. a ereat disservice (8).Indeed electronic c&figurations represent an approximation that is inconsistent with quantum mechanics. Even in the days of the earlier quantum theory, Bohr frequently admitted that it is incorrect to ascribe stationary states to individual electrons (9). This is precisely what is involved in the use of electronic configurations for atoms. In quantum mechanics i t can be shownhuite categorically that for a many-electron atom the individual electrons are not in stationary states

1. Mazurs. E.G.GrophieolRapresantoliom o/ths Periodic Table dvringon. Hundred Yews; Universityof Alabama: Alabama, 1974. B. J. Chem.Educ. 1982.58.634. 5. Jensen, 6. Nelson, P.G.Educ. Chem. 1988,26,185. 7. Jargensen,C.K.Angeru. Chsm.Inf.Edn.Ew1. 1973,12,12. 8. Sce.ri.E. RNemSci. 1989,1651.76. 9. Bohr. N . Coll~etedPapers; Nielsen, J.Rud. Ed.; North Holland: Amsterdam. 1977. 10. Scerri,E. R. J . Chem.Edu, 1989,66,481. 11. Carpenler,A. K. J. Chrm. Edur. 19.93.60.562. 12. Hovland, A.K. J. ChemEduc. 1986,63,6W. 13. Strong. J.J. Cham. Educ 1986.63.84.

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Eric R. Scerrl King's College London University London S W 3 BLX, England

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Surely we have already seen enough schemes aimed a t learnine the electronic confieurations in the chemical education jo;rnals. The fact t h a i learning electronic configurations bas become an end in itself is deplorable, and yet so

712

Journal of Chemical Education

What's the Use To the Editor:

In his interesting feature on the element carbon [J.Chem. Educ. 1990, 67, 1091, Alton Banks incorrectly has asserted that, " . . . [carbon] forms more compounds than all other elements combined!' Anton Burg pointed out to graduate students a t the University of Southern California in the 1950's that the vast majority of all carbon compounds also contain the element hydrogen, and that there is in addition a plethora of hydrogen compounds that do not contain any carbon. F. Albert Cotton and Geoffrey Wilkinson ( I ) similarly note that, "Hydrogen forms more compounds than any other element and hydrogen compounds of all elements excepting the noble gases are known." Literature Clted 1. Cotton, F. A,: Wilkinson. G. Aduaneedlnorgonir Chemistry, Sthod.; Wiley: New York, 1988: p 88.

Erne* R. Blrnbaum St. John's University New Yoh. NY 1 1 4 3 9

To the Editor:

In a desire to point out the multitudinous compounds of carbon. I fell into a common tran. i.e.. a failure to remember hydrogen's role in compounds: 1 thank Birnbaum for his note calling that fact to our aggregate attentions. ~~

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Anon J. Banks Sournwest Texas State University SBn MB~COS. TX 7 8 6 6 6