Identify the correct statements from the following : I. Tendency to form halide hydrates gradually increases from Be to Ba down the group. II. Tendency to form stable super oxides increases from ( Li ) to ( Cs ) down the group. III. Low solubility of ( LiF ) is due to its high lattice energy. IV. Solubility of carbonates of group-2 elements increases down the group.

Step-by-step solution

(II) On moving down in the group the size of the atom increases. The positive charge around the ion gets weaken. The bigger atom can stabilise the bigger superoxide ion with less negative field. (III) Due to smaller size of ( F ⁻ )ion, the lattice energy increases. While, hydration enthalpy is less than that of lattice energy. Hence, LiF has very low solubility. Statements (II, III) are correct. Thus, correct option is (c).