This page explains how antifreeze in a radiator prevents engine freezing and discusses determining the molar mass of an unknown solute via freezing point depression. By measuring the freezing point ch...This page explains how antifreeze in a radiator prevents engine freezing and discusses determining the molar mass of an unknown solute via freezing point depression. By measuring the freezing point change after dissolving a known mass of solute, one can calculate molality and moles of solute, leading to a calculated molar mass of 59.7 g/mol in an example.