Question

what are following steps​

Answer 1

Period Number = Number of shells

Group Number = Number of Valence Electrons (when the number of Valence Electrons are 1 or 2.)

Group Number = 10 + Valence Electrons (when Valence Electrons are greater than 2.)

Now, For example,

Find the position of Sodium in the Modern Periodic Table.

Sol:-  Atomic Number of Na = 11

        Electronic Configuration = 2,8,1

        Number of Shells = 3 = Period Number

        Number of Valence Electrons = 1 = Group Number.