(i) Place the representative elements of group 1 and 2 on the left hand side and those of group 13- 18 on the right hand side in the same way as they appear in the traditional long form of the Periodic table. Divide the space between these 2 sets of the representative elements into 2 parts. on the left Part, place the inner transition elements in 2 horizontal series of 14 elements each, the first Horizontal series which lies in the 6th period consist of 14 Lanthanoids (Z=57-70) while the second horizontal series which lies in the 7th period also consists of 14 Actinoids(Z=89 to 102).
On the right part, place the transition elements in 4 horizontal series of 10 elements each: first series with Z = 21 to 30 lies in the fourth period, second series with Z = 39 to 48, lies in fifth period, 3rd series, with Z = 71 to 80 lies in the sixth period and 4th series with Z = 103 to 112 lies in the 7th period. The outlines of the extended version of the periodic table thus obtained are shown below.
(ii) Although in the extended version of the periodic table, elements are arranged in increasing order of their atomic numbers without any discontinuity, but it has the following two discrepancies. Elements La (Z= 57) and Ac (Z= 89) are considered as inner transition elements. But in traditional long form they are considered as transition elements. Elements Lu (Z= 71) and Lr(Z= 103) are considered as transition elements but in the long form, they are considered as inner transition elements.
