Revised Atomic Form Periodic Table Frederick C. Strong Ill Faculdade de Engenharia de Alimentos e Agriola, Universidade Estadual de Campinas, C.P. 6121, 13100 Campinas, SP., Brasil
I have learned that a number of chemists have made use of my Atomic Form Periodic Table, published in THIS JOURNAL in 1959.' Since then, seven new elements have been synthesized (No, Lr, Rf, Ha, and elements 106,107, and log),the fmt completing the 5f orhital and the others starting a new 6d orhital. Besides this addition, a major modification has been made in the table-shifting the positions of the lanthanides and actinides to the s h e l l s ~ h e must r ~ of the elements have the electron added and considering those fur whirh this is not Strong, Frederick C., Ill, J. CHEM. EDUC., 36,344 (1959). Rudurf. Georg, "Das periodische System, seine Geschichte und Bedeutung fiir de chemische Systematik." Voss, Hamburg, 1904, p. 247. Also in Mazurs. Edward G.. "Types of Graphic Representation of the Periodic System of Chemical Elements," University of Alabama Press. 1974, p. 4. Janet, Charles, Bauvais, November 1928: Mazurs, p. 141. Sibaya, L., Amer. J. Phys., 9, 122 (1941):Mazurs, p. 157. Flores Cabral, A.. "Elementos de Quimica Electrbnica," Boletim DidAtico da Escola de Agronomia Eliseu Maciel, Pelotas. Brasil, 1958, (separatetable): Mazurs. p. 70. Overly simplified,because only s orbitals are spherical, or circular in cross section.
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so as exceptions. These exceptions are indicated. The table is reproduced here, together with instructions for its interpretation. I am grateful to Euripides Assump@o for his excellent drawing of the table. In an introduction to a hook on the periodic system, George Rudurf wrote? It should he stronelv recommended that evervone who wants to derive a new furrn;; table should first take the trouble t o examine theearlier literatureabout thisaubjrct; in this wav, many unnecessary repetitions of idcns already given at an earlier period can he avoided. While I should have done this in my earlier paper, I would like to give some references a t this time, even though my table was developed independently. Janet3 nuhlished a similar mancement..exceot that his was in a spiral form. However, a spiral is purely a geometric shape of convenience and does not have the atomic structure basis of a circular table. Sihaya4and Cabra15used concentric circles, hut located the transition elements on radii in between the radii fur the elements before them. As Mazurs says oiSihaya's table, "This table is not ronvenient fur reading."
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How to Use the Table The table is in the form of an atom,6 with the orbitals (s,p,d,f) and the shells (1-7) indicated. The electronic structure of the atom of any element can be ohtained by considering every symbol, up to and including the element in question, as an electron. Some modifications of this procedure for individual elements are described below. Each element has two numbers, one Arabic and one Roman, placed a t the ends of the radius on which the symbol of the element is located. These indicate, in general, the range of oxidation states of the element.
Irregular Structures 46Pd has two electrons in the 4d orbital and no electrons in 5s. 57La and u G d have one electron in the 5d orbital and one less in 4f. mTh has two electrons in the 6d orhital and none in 5f. Elements indicated with a dot (.) have only one electron in the outer s orhital and one more electron in the d orbital containing the element symbol. Elements marked with a daeeer (t) have one electron in the 6d orhiKil a i d one less electron in 5 f .
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Journal of Chemical Education
