Cryoscopic constant
In thermodynamics, the cryoscopic constant,, relates molality to freezing point depression. It is the ratio of the latter to the former:
Through cryoscopy, a known constant can be used to calculate an unknown molar mass. The term "cryoscopy" comes from Greek and means "freezing measurement." Freezing point depression is a colligative property, so depends only on the number of solute particles dissolved, not the nature of those particles. Cryoscopy is related to ebullioscopy, which determines the same value from the ebullioscopic constant.
The value of, which depends on the nature of the solvent can be found out by the following equation:
The for water is 1.853 K kg mol−1.