A New Periodic Table HENRY A. WAGNER with HAROLD SIMMONS BOOTH Western Reserve University, Cleveland, Ohio
T.
HE periodx table described in this paper was de. . msed m t h the aim of revealing in a simple and direct manner the relations of the properties of the elements and their electronic configurations. The elements are arranged on the basis of an isosceles triangle with hydrogen, atomic number 1, a t the apex, and in increasing order of atomic numbers as usual. This expanding triangular arrangement permits of placing the rare earths in their proper position in period number 6 and correctly places the so-called transition elements as well. The elements are divided into horizontal periods as determined by their main quantum groups. Each period, save the first, begins with a rare gas, being a peculiarly appropriate position for elements with normal zero valence. Continuous sloping lines connect the elements of the different periods which have the same electron arrangement in their incomplete quantum shells and consequently connect the elements with closely similar physical and chemical properties, usually spoken of as "families." Discontinuous lines connect elements and families of secondary similarity, that is, the so-called
A and B subgroups. These lines also show where each element belongs in the original Mendele& table. The four different types of elements, as classified &y Bohr according to the number of incomplete quantum groups,. are indicated in the table by four ditferent types of circles, in which the symbols of the elements are placed. The electron arrangement for any element may be obtained by: (1) observing its period number a t the left of the period; (2) referring to the table a t the upper left of the table to obtain the electron arrangement in the completed quantum orbits; and (3) following the continuous sloping lines from the element to the bottom of the table and reading the electron arrangement of the electrons X, Y, and Z, or X and Y and 2. Some examples are given below: Element At. No. K L M N 0 P O '
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The maximum covalence number (Werner's co-
, ordination
number) for each period is placed a t the right of the period. The minimum and the maximum valence for a group are shown a t the bottom of the table with a ) to show intermediate valence changes by one unit, and with)) to indicate intermediate valence changes by two units. The placing of hydrogen a t the apex of the triangle tied to both the alkali metals and the halogens by continuous lines illustrates strikingly the close cfiemical
similarity of hydrogen to both groups one and seven. In a large wall table of this design the circles could be colored the same as those of solutions of the stable ion of the element thus showing even more strikingly the relation between incompleteness of electron groups and ion color. However, to make the table reveal more properties would probably, as has been too often done in the past, make i t so complicated as to conceal rather than reveal relationships.
