Important Relations Concerning Depression in Freezing Point
(1) Depression in freezing point is directly proportional to the lowering of vapour pressure.
Where molal depression constant or cryoscopic constant; Molality of the solution (i.e., no. of moles of solute per of the solvent); Depression in freezing point
Where is molal depression constant and defined as the depression in freezing point produced when 1 mole of the solute is dissolved in of the solvent. and are the weights of solute and solvent and is the molecular weight of the solute.
Where Normal freezing point of the solvent; Latent heat of fusion/g of solvent; for water is