Editing Molality (section)

{{Short description|Amount of substance of solute divided by the mass of the solvent}}
{{Distinguish|Molarity}}

In [[chemistry]], '''molality''' is a measure of the [[amount of substance|amount of solute]] in a [[solution (chemistry)|solution]] relative to a given [[mass]] of solvent. This contrasts with the definition of ''[[molarity]]'' which is based on a given [[volume]] of solution.

A commonly used unit for molality is the [[Mole (unit)|moles]] per [[kilogram]] (mol/kg). A solution of concentration 1&nbsp;mol/kg is also sometimes denoted as 1&nbsp;'''molal'''. The unit mol/kg requires that [[molar mass]] be expressed in kg/mol, instead of the usual g/mol or kg/kmol.