Property of the alkaline earth metals that increases with their atomic number is

Options

A. solubility of their hydroxides in water
B. solubility of their sulphates in water
C. ionisation energy
D. electronegativity

Answer

A

Explanation

Solubility of hydroxides of alkaline earth metals increases because both the lattice energy are hydration energy decrease down the group are the size of the cation increase but lattice energy decrease more rapidly than the hydration energy and hence the solubility increases down the group.
Among sulphates, since size of `SO_4^(2-)` ion is very big as compared to the metal cation, therfore, lattice energy remains the almost constant but their hydration energy decrease downt the group of course electronegatively and ionization energy both decrease down the group as the atomic size increase.