Question

Sodium sulphate is soluble in water whereas Barium sulphate is sparingly soluble because :

• A. The hydration energy of sodium sulphate is less than its lattice energy
• B. The lattice energy of Barium sulphate is more than its hydration energy
• C. The lattice energy has no role to play in solubility
• D. None of these

Answer 1

The correct option is B The lattice energy of Barium sulphate is more than its hydration energy

$BaS{O}_4$ is sparingly soluble in water because its hydration energy is lesser than the lattice energy and thus ions are not separated from each other. On the contrary in $N{a}_{2}S{O}_4$, the hydration energy is more than its lattice energy. Thus ions are separated from each other and pass in solution state.