Molality Calculator – Moles per Kilogram of Solvent
Calculate molality in mol/kg from moles of solute and solvent mass in kilograms.
Molality expresses the amount of solute relative to the mass of the solvent rather than the total solution volume. The implemented calculator uses moles and kilograms of solvent.
How it works
m = n / mass(solvent), where n is moles of solute and solvent mass is in kilograms.
Example
0.5 mol of solute in 2 kg of solvent gives 0.25 mol/kg.
How to use
- Enter moles of solute.
- Enter solvent mass in kilograms.
- Calculate molality.
- Review the result in mol/kg.
Key features
- Moles and kilogram inputs
- mol/kg output
- Positive solvent-mass validation
- Direct definition-based calculation
Common uses
- Chemistry concentration exercises
- Solution-preparation checks
- Comparing molality examples
Frequently asked questions
Is molality the same as molarity?
No. Molality uses kilograms of solvent, while molarity uses litres of solution.
Can solvent mass be zero?
No. The calculation divides by solvent mass, so a positive value is required.
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