Question

define for me please

Answer 1

Define me is nothing but about you

Answer 2

electronic configuration of magnesium is

1s^2 2s^2 2p^6 3s^2.

it has 2electrons in its outermost shell


electronic configuration of calcium is

1s^2 2s^2 2p^6 3s^2 3p^6 4s^2

it also has 2 electrons in its outermost shell

hence they are in same group


they also similar chemical properties and valency{+2}