Question

Why freezing point is depressed when solute added in to a solvent?

Answer 1

The freezing point of the solvent in a solution changes as the concentration of the solute in the solution changes (but it does not depend on the identity of either the solvent or the solute(s) particles (kind, size or charge) in the solution).

Answer 2

The presence of solute lowers the freezing point if any solvent; this effect is called freezing point depression. the key to understand this effect is that the solute present in the liquid solution, but not in the pure solid solvent.

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