Question

In alkaline earth metal sulphates, the value of hydration energy decreases down the group because of the :

• A. decrease in size
• B. increase in size
• C. greater lattice energy
• D. none of the above

Answer 1

The correct option is B increase in size

Smaller the ion, higher will be the hydration enthalpy because smaller atoms can accommodate a large number of water molecules around it, and gets highly hydrated.

Hydration enthalpy decreases down the group because down the group size of the atom increases because of the addition of extra valence shells.