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

Explanation

IE: In groups and periods of the periodic table the ionization enthalpy values are periodically change depend upon the electronic configuration and size of elements.
In a group of elements ionization energy decreases from top to bottom because atomic radius increases. In general, in a period the atomic size decreases. Because of this, the ionization energy increases across a period.