Question

which of the following is an example of soluble salts?
(A) Salts of sodium
(B) Salts of potassium
(C) Salts of ammonium
(D) All of the above

Answer 1

Soluble salts are the ionic compounds which are able to dissolve in water. They have the tendency to get dissociated into their ions during the interaction with the solvent. The salt can be formed by reacting acid with metal or acid with carbonate or acid with alkali or acid with base metal.

Complete step-by-step answer: Generally the salts which are formed by reacting alkali metals are soluble in water. The salts which are formed by reacting with chlorides, bromides and iodides are soluble. While the salts formed by carbonates, sulphides and oxides are insoluble. The rules which are general for predicting the solubility of salts are the following:
1.All the common salts of sodium are soluble
2.All the common salts of potassium are soluble
3.All nitrate salts are soluble
4.All ammonium salts are soluble
5.Common sulphate salts are soluble except that of calcium and barium
6.Common carbonates salts are insoluble except that of sodium, potassium and ammonium.
Ammonium, potassium and sodium salts are soluble in water because they completely dissociate in the solution.

So the correct option is option (D).

Note: in practice there are some salts which are considered as insoluble but they do get actually slightly ionized in water by releasing ions in solution. The solid which is not dissolved will come in contact with water and will come into equilibrium with ions it has released. At this point the solution is said to be a saturated solution.