overmætning

Overmætning refers to a state where a solution contains more dissolved solute than it can normally hold at a given temperature and pressure. This phenomenon occurs when a solution is carefully cooled or when solvent is evaporated without disturbing the dissolved solute. The excess solute remains in solution, but it is in an unstable state.

This unstable condition makes over-saturated solutions highly sensitive to external stimuli. The introduction of a seed crystal, a tiny fragment of the solute, can trigger rapid crystallization of the excess solute. Agitation or even a sudden change in temperature can also induce crystallization.

Overmætning has practical applications in various fields. In chemistry, it is used in recrystallization techniques to purify solid compounds. The process involves dissolving an impure solid in a hot solvent until it is saturated, then allowing the solution to cool. As the solution cools and becomes over-saturated, the desired compound crystallizes out, leaving impurities behind in the solution. In the food industry, it is relevant to processes like candy making, where careful cooling of sugar solutions leads to specific crystalline structures. Understanding overmætning is crucial for controlling crystallization processes and achieving desired product properties.