The solubility of alkaline earth metal sulphates in water decreases in the order . What is the prima — s Block Elements Chemistry Question

💡 Solution & Explanation

For alkaline earth metal sulphates, the lattice energy remains relatively constant down the group due to the large size of the sulphate anion dominating the packing. However, the hydration enthalpy of the metal cations ($M^{2+}$) decreases drastically as the cation size increases from $Be^{2+}$ to $Ba^{2+}$. This rapid drop in hydration enthalpy is responsible for the decrease in solubility.