Write short note an freezing point depression in freezing point and cryoscopic constant.

Explanation

(i) Freezing point is difined as the temperature at which the solid and the liquid states of the substances have the same vapour pressure.
(ii) When a non volatile solute is added to water at its freezing point, the freezing point of water is lowered from `0^(@)C.` The lowering of freezing point of the solvent when a soute is added is called depression in freezing point `Delta T_(f).`
(iii) `Delta T_(f) = T_(f)^(@) - T_(f)`