Periodic system of the elements

Abstract

The chemical and physical properties of the elements are functions of their atomic weights, in the periodic system of elements. The periodicity is all embracing and complete extending to practically all properties. However, if an attempt is made to represent this periodicity graphically, in tabular form, it is a failure. The usual form of representation is given in the table, Fig. I , where however the last column again precedes the first column, that is, the representation should be on a cylinder, with Li following He, and Na following Ne, etc., or on a spiral.The first period of 8 elements, from Li to Ne, is followed by the second period of 8 elements, from Na to A, which are close homologs of tlre first period. The third period starts with A, K and Ca, close homologs of the corresponding elements of the first 2 periods, but gradually the analogy becomes less in V, Cr, Mn, though there still are some analogies to the corresponding elements of the preceding periods:Then, in the triplet Fe, Co, Ni, the analogy with Ne and A entirely disappears. Tkea a partial analogy appears again in Cu, Zn, as sub groups of K, Ca, &finally, a t the end of this period, in Se, Br, Kr, close homologs with S, (31 and A are again reached. We thus here have a double period of 18 b e n t s . Then follows a second double period of 18 elements from Kr to I. -Plotted in a table of 8 columns, Fig. I , this double periodicity L not represented, and each column does not contain a series of homologs,