How does the ionization energy vary in a group and a period ?

How does it very in a group and in a period ?

Define Ionization energy .

The ionization energy is _______

How does the electron gain enthalpy values vary in a group and a period ?

How does the valency vary on going down a group ?

What is periodic property? How the following properties vary in a group and in a period? Explain. Metallic character.

What is a periodic property? How the following properties vary in a group and in a period? Expain (a) Atomic radius.

What is a periodic property? How the following properties vary in a group and in a period? Explain (b) EN.