ΔTb = Kb × m × i
Boiling point elevation is a colligative property — it depends only on the number of solute particles, not their identity. Adding any non-volatile solute to a solvent raises the boiling point because solute particles reduce the vapor pressure of the solvent. Kb for water is 0.512°C/m. The van't Hoff factor i accounts for dissociation: NaCl → Na⁺ + Cl⁻ gives i = 2, CaCl₂ gives i = 3. A 1 m NaCl solution elevates water's BP by 0.512 × 1 × 2 = 1.024°C. Practical applications: adding salt to pasta water raises the BP only ~0.17°C per tablespoon per liter — negligible for cooking. Automotive antifreeze (ethylene glycol) significantly raises coolant BP to prevent boil-over.