0The elements are classified as S P D F blocks based which shells there valance electrons enters.
When we comparing the periodic properties
Atomic size : As no shells increases size also will increases that's down the GP size will increase and left to right decrease since the nuclear charge will increase ,so orbital will come closer to size will decrease.
Ionization energy will decrease down the GP and increases towards right .since the electron are held closer more energy is required.
Electron affinity will maximum for halogen decrease towards alkyl gp.
