Question

15. Which of the following do not have the same number of valence electrons ? (a) H, Li, Na, K (b) He, Mg, Be, Ca (c) B, AI, N, P (d) O, S, Se ​

Answer 1

Answer:

(c) B, Al, N, P. is the correct answer.

Explanation:

valency of B, Al =3

where as N,P = 5

so this right option