Osmotic concentration, formerly known as osmolarity,[1] is the measure of solute concentration, defined as the number of osmoles (Osm) of solute per litre (L) of solution (osmol/L or Osm/L). The osmolarity of a solution is usually expressed as Osm/L (pronounced "osmolar"), in the same way that the molarity of a solution is expressed as "M" (pronounced "molar"). Whereas molarity measures the number of moles of solute per unit volume of solution, osmolarity measures the number of osmoles of solute particles per unit volume of solution.[2] This value allows the measurement of the osmotic pressure of a solution and the determination of how the solvent will diffuse across a semipermeable membrane (osmosis) separating two solutions of different osmotic concentration.
- ^ McNaught, A. D.; Wilkinson, A.; Chalk, S. J. (1997). IUPAC. Compendium of Chemical Terminology (the "Gold Book") (2nd ed.). Oxford: Blackwell Scientific Publications. ISBN 0-9678550-9-8. Retrieved 23 January 2022.
- ^ Widmaier, Eric P.; Hershel Raff; Kevin T. Strang (2008). Vander's Human Physiology, 11th Ed. McGraw-Hill. pp. 108–12. ISBN 978-0-07-304962-5.