Higher the hydration energy of the ions greater is the solubility of the compound in water. why?
What is hydration: Hydration, also sometimes called dissolution, is the process of attraction and association of molecules of a solvent with molecules or ions of a solute.
Hydration Energy is the amount of energy released when one mole of gaseous ions combine with water to form hydrated ions.
M+ (g) + aq â M+ (aq) + hydration energy
X- (g) + aq â X- (aq) + hydration energy
Higher the hydration energy of the ions, greater is the solubility of the compound in water. As ions dissolve in a solvent they spread out and become surrounded by solvent molecules.
Further, the extent of hydration depends upon the size of the ions. Smaller the size of the ion, more highly it is hydrated and hence greater is its hydrated ionic radius and less is its ionic mobility (Conductance).
We hope that clarifies your query.