ΔTb = Kb · bBΔTb, the boiling point elevation, is defined as Tb (solution) - Tb (pure solvent).Kb, the ebullioscopic constant, which is dependent on the properties of the solvent. It can be calculated as Kb = RTb2M/ΔHv, where R is the gas constant, and Tb is the boiling temperature of the pure solvent [in K], M is the molar mass of the solvent, and ΔHv is the heat of vaporization per mole of the solvent.bB is the molality of the solution, calculated by taking dissociation into account since the boiling point elevation is a colligative property, dependent on the number of particles in solution. This is most easily done by using the van 't Hoff factor i as bB = b solute · i. The factor i accounts for the number of individual particles (typically ions) formed by a compound in solution.