Assign the position of the element having outer electronic configuration (i) ns^(2)np^(4) " for " n = 3 (ii) (n -1) d^(2)ns^(2) " for " n = 4and (iii) (n -2) f^(7) (n -1) d^(1) ns^(2) " for " n = 6,in the periodic table.

Assign the position of the element having outer electronic configurati

1.	Assign the position of the element having outer electronic configuration (i) ns^(2)np^(4) " for " n = 3 (ii) (n -1) d^(2)ns^(2) " for " n = 4and (iii) (n -2) f^(7) (n -1) d^(1) ns^(2) " for " n = 6,in the periodic table.
Answer» <P> Solution :For n = 3, the element belongs to third period. The electronic configuration is `3d^(2) 3d^(4)`. Since the last electron enters p ORBITAL, therefore, the element belongs to p-blcok, Group no, of the element, ` = 10 + ` No. of electron in valence shell ` = 10 + 6 = 16` ` :. ` Period = 3 , group = 16 (ii) For n = 4, the element belongs to fourthperiod. The electronic configuration is`3d^(2) 4s^(2)`. Since the d-sub-shell is incomplete, the element belongs to d-block. Group no, of the element, = No. of electron in `(n -2)` subshell ` + ` No. of electron in ns subshell ` = 2 + 2 = 4` ` :. ` Period = 4, group = 4 (III)For n = 6, the element belongs to SIXTH period. The electronic configuration is`4f^(7) 5d^(1) 6s^(2)`. Since the electron goes to f -orbital, therefore, its belongs to f-block. All f-block elements belongs to group-3. `:. `Period = 6, group = 3