Question

Assign the position of the element having outer electronic configuration 

(i) ns² np⁴ for n=3 (ii) (n-1) d² ns² for n=4 (iii) (n-2)f⁷ (n-1)d¹ ns² for n=6

Answer 1

(i) n= principal no. which shows no of periods. N=3 so E.C =3s23p4=elements having position 3rd period 16th group. 

(ii) n=4 so elements belong in 4th period .it is d block element .d2= 2 electron in d orbital it belongs to 4th group in d block. 

(iii) n=6 and electron goes in fshell, so it is f block element having 6th period and 7th element of lanthanides series.