Answer : Electron affinity (Eea) of an atom or molecule can be defined as the amount of energy released or spent when an electron is being added to a neutral atom or molecule in the gaseous state to form a negative ion.
Chlorine is considered to be the element which has highest electron affinity in the modern periodic table.
The general formula is X + ---->
+ energy
It is found that nonmetals have more positive Eea than metals.
Electron affinity increases across the group from left to right in the modern periodic table. Elements with small nucleus have high electron affinity.