Question

Why solubility of alkaline earth metal compounds are comparatively less than the corresponding alkali metal compounds in water?

Answer 1

bcoz the alkali metals have more free ions in comparison to the alkaline earth metals......

Answer 2

Solubility of alkali metal compounds and alkaline earth metal compounds can be compared depending on two factors- i) size ii) lattice enthalpy

                                   Solubility ∝ size

                                  Solubility ∝ 1/ lattice enthalpy

Alkaline earth metals have smaller size as compared to alkali metals. Hence they are less soluble in water.

Higher the lattice enthalpy, lower the solubility. Alkaline earth metals have high lattice enthalpy resulting in their lower solubility.