Boiling-point elevation is a colligative property that states that a solution will have a higher boiling point than that of a pure solvent after the addition of a dissolved solute. The change in boiling point can be determined by the equation ΔTB.P.=i·Kb·m, where i is the Van 't Hoff factor (the number of dissolved particles the solute will create when dissolved), Kb is the ebullioscopic constant unique to each solvent, amd m is the molality of the solute.
A common mis-attribution of the use of boiling-point elevation is adding salt when cooking foods to elevate the temperature of the water before it boils. However, the temperature increase caused by the amounts of salt added when cooking is generally not enough to raise the temperature by a single degree, as a comparison, seawater has a boiling point of 100.6°C. The salt is added simply to season the food and prevent pasta from sticking.
A somewhat more involved derivation of the boiling-point elevation formula.