Compare the solubility and thermal stability of the following compounds of the alkali metals with those of the alkaline earth metals
Sulphates of both group 1 and group 2 metals are stable towards heat.
Sulphates of alkali metals are soluble in water. However, sulphates of alkaline earth metals show varied trends.
BeSO4 Fairly soluble
CaSO4 Sparingly soluble
In other words, while moving down the alkaline earth metals, the solubility of their sulphates decreases.
Sulphates of group 1 are soluble in water except Li2SO4. They are thermally stable.
Solubility of sulphates of group 2 decreases down the group because Lattice energy dominates over hydration energy.
Sulphates of group 2 elements are thermally stable and increasing down the group due to increases in Lattice energy.