Question

element P,Q,R,and S have atomic numbers 15,16,17,and18 respectivelywhich of there is a non metal with valancy 1 option (i) P (ii) Q (iii) R (iv) S​

Answer 1

Answer:

Chlorine _17_R because if we do electronic configuration of chlorine then we get 2,8,7

We know the valency

Valency= No. of valence electrons

=8-7=1

That's why i said chlorine