Boiling Point Elevation Calculator

Why dissolved particles raise the boiling point

Boiling point elevation is a colligative property, which means the size of the effect depends mainly on how many dissolved particles are present rather than on their identity. Adding solute lowers the solvent's escaping tendency, so the solution must be heated slightly more to reach the same vapour-pressure condition as the pure solvent.

For dilute ideal solutions, the shift is proportional to particle molality. That is why the calculator reports both the molality and the effective particle molality i × m side by side.

Formula used here

This page uses the standard dilute-solution relation ΔTb = iKb m. Kb is the solvent's ebullioscopic constant, m is solute molality in mol/kg solvent, and i is the van't Hoff factor that approximates how many particles each dissolved unit contributes.

Worked example

For a 1.00 m nonelectrolyte in water, Kb = 0.512 °C·kg/mol and i ≈ 1, so the boiling point elevation is 0.512 °C. The solution therefore boils at about 100.512 °C at the same 1 atm reference pressure.

If the solute dissociates, the effective particle count rises and the boiling point shift grows. That is why sodium chloride produces a larger elevation than glucose at the same formal molality.