Excess pressure required to maintain osmotic equilibrium between a solution and the pure solvent separated by a
membrane permeable only to the solvent:
where
,
are the partial molar volume and activity of solvent
for an incompressible fluid. For ideal dilute solutions,
,
where entities
are individually moving solute molecules, ions, etc., regardless of their nature,
,
are the amount and mass concentration of the solutes, and
is the mass average molar mass of the solutes. The amount is sometimes expressed in osmol (meaning a
mole of osmotically active entities), but this usage and the corresponding term
osmolarity are discouraged.
Source:
Cite as:
IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997). XML on-line corrected version: http://goldbook.iupac.org (2006-) created by M. Nic, J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8.
doi:10.1351/goldbook.
