Question

thethe electronic configuration of elements a b c and d are given under A1 A1 b2 13282 de to first which among the following belongs to same group name it second which among which among them belong to same period name it which among third which among the following is in art name it​

Answer 1

Answer:

Element with electronic configuration 2,8,2 belongs to 3rd period and 2nd group. The valence electrons give us the idea of group number. As the electrons are divided into 3 different shell therefore period number is 3.