Question

How does a solvent affect the solubility of an ionic compound?

Answer 1

Well, the number of solvents that are capable of solvating ionic solutes is fairly small.

Explanation:

Water is an exceptionally powerful solvent, and MOST solutes, ionic or not, have SOME solubility in an aqueous medium to a greater or lesser degree.

Water is a polar, protic solvent that is capable of solvating both positive ions and negative ions. When we dissolve a salt, say common salt in water, we write...`NaCl(aq)`...we really mean something of the order of `[Na(OH_2)_6]^+` and `[Cl(H_2O)_(4-6)]^-`...this is what mean when we speak of aquated ions. A couple of solvents capable of solvating ionic solutes are `HF`, and `NH_3`, and both of these are protic polar solvents (tho they are certainly not as convenient as water to use!).

On the other hand, organic solvents, ethers, alkyl halides, even alcohols, have next to no capacity to dissolve ionic solutes...because these solvents are grossly incompetent to solvate ions.