Question

Why should an ionic solute be INSOLUBLE in water?

Answer 1

Well, clearly, the force of attraction between anion and cation IS GREATER than the interaction between solvent and the solvated ion....

Explanation:

And if we look at aqueous solubility, carbonates, phosphates, sulfides, and oxides, whatever the cation, TEND to be insoluble in water. And why? Because for these anions, which have a greater than unit charge, necessarily have a greater degree of electrostatic interaction, which can be clearly appreciate from `"Coulomb's law..."`

..i.e. `F=(k_e*q_1q_2)/r^2`, where `q_1,q_2` are the charges, and `r` is the distance that separates them......

Of course, aqueous solubility is an experimental phenomenon...