A solution contains 55 g solute in 100 g water while normal solubility is 45 g. What may happen when a small crystal is added?
At the stated temperature, 45 g is the normal equilibrium limit for 100 g water, but 55 g is present. The solution is therefore supersaturated by about 10 g. A seed crystal provides a nucleation surface, so excess solute may crystallize until roughly the normal limit remains dissolved. The exact separated amount can depend on conditions.