Molality calculator
Find moles of solute per kilogram of solvent.
Formula
n = solute mass (g) / M (g/mol); molality = n / solvent mass (kg)
Solute mass: 10 g · Solvent mass: 0.5 kg · Solute amount ≈ (10 g × 0.001 kg/g)×1000÷(100) · Molality ≈ (0.1)÷(0.5 kg)
How to use
- Enter the pure solute mass.
- Enter its molar mass and the solvent mass.
- Read molality in mol/kg.
Examples
- 10 g at 100 g/mol in 0.5 kg solvent gives 0.2 mol/kg.
Frequently asked questions
Solvent or solution mass?
Use solvent mass alone, excluding the solute.
How is molality different from molarity?
Molality uses kilograms of solvent; molarity uses liters of final solution.
Does temperature change molality?
It stays unchanged if solute and solvent masses stay constant.
Sources
Updated: