Answer : Precipitation occurs when the product of the ion concentrations exceeds the
.
Explanation :
Ionic product : It is the product of the concentrations of the ions in solution raised to the same power by its stoichiometric coefficient in a solution of a salt. This takes place at any concentration. The ionic product is represented as, Q.
Solubility product constant : It is defined as the product of the concentration of the ions present in a solution raised to the power by its stoichiometric coefficient in a solution of a salt. This takes place at equilibrium only. The solubility product constant is represented as,
.
There are three cases for the solubility :
- When
this means that the solution is unsaturated solution and more solid will be dissolve. - When
this means that the solution is saturated solution. - When
this means that the solution is supersaturated solution and solid will be precipitate.
Hence, the precipitation occurs when the product of the ion concentrations exceeds the
.