Question

formation of cation is endothermic where formation of anion is exothermic. justify

Answer 1

The formation of cation is anendothermic reaction because to form a cation you need to supply heat. ... This heat would eject the electron from the atom. So hence supplying heat means endothermic reaction. On the other hand formation of anion is anexothermic

Answer 2

The formation of cation is an endothermic reaction because to form a cation you need to supply heat.
This is because a cation means loosing electrons to gain +ve charge.
Loosing electrons means removing those electrons from the respective atom.
To remove electron we need to supply heat. This heat would eject the electron from the atom.
So hence supplying heat means endothermic reaction.

On the other hand formation of anion is an exothermic reaction.
The following reaction is exothermic because the heat is released when we add electrons in the atom.