Group II elements form more hydrated salts than group I elements because group II elements have a lesser atomic radius than the corresponding group I elements. Lesser is the size of an atom more will be it's hydration energy. Due to this reason group II salts are mostly hydrated. 

Introduction:
The hydration of salts refers to the process in which water molecules surround and bond with the ions present in the salt. The degree of hydration depends on the charge and size of the ions. Group II elements (alkaline earth metals) and Group I elements (alkali metals) have different properties that result in the difference in the hydration of their salts.

Size and Charge of Ions:
- Group II elements have larger ions compared to Group I elements. This is because as you move down the periodic table, the atomic radius increases. The larger size of the Group II ions allows for more water molecules to surround and bond with them, resulting in greater hydration.
- Group I elements have smaller ions due to their smaller atomic radii. The smaller size restricts the number of water molecules that can surround and bond with the ions, leading to lower hydration compared to Group II salts.

Polarizing Power:
- Group II elements have higher polarizing power compared to Group I elements. Polarizing power refers to the ability of an ion to distort the electron cloud of a neighboring water molecule. The higher the polarizing power, the stronger the attraction between the ion and the water molecule.
- The larger size and higher charge density of Group II ions contribute to their higher polarizing power. This leads to stronger interactions between the ions and water molecules, resulting in greater hydration.

Hydration Enthalpy:
- The hydration enthalpy is the energy released when the ions in a salt are hydrated. It is influenced by the charge and size of the ions.
- Group II ions have higher hydration enthalpies compared to Group I ions. This is because the larger size and higher charge of Group II ions allow for more effective interactions with water molecules, releasing more energy.
- The higher hydration enthalpies of Group II ions indicate that more water molecules are involved in the hydration process, resulting in greater hydration compared to Group I salts.

Conclusion:
In conclusion, salts of Group II elements are much more hydrated compared to salts of Group I elements due to the larger size and higher charge of Group II ions. The larger size allows for more water molecules to surround the ions, while the higher charge and polarizing power enable stronger interactions between the ions and water molecules. These factors result in higher hydration enthalpies for Group II salts, indicating a greater degree of hydration.