Dilute-solution osmotic pressure
For an ideal dilute solution separated from pure solvent by a solvent-permeable membrane, osmotic pressure is approximately the molar concentration of osmotically active solute particles times RT.
Key knowledge
For an ideal dilute solution separated from pure solvent by a solvent-permeable membrane, osmotic pressure is approximately the molar concentration of osmotically active solute particles times RT. Dissociation, association and nonideal interactions can change the particle accounting and pressure.
Values and equations
Π ≈ cparticles RT
- Π
- osmotic pressure Pa
- cparticles
- molar concentration of osmotically active particles mol m⁻³
- R
- molar gas constant J mol⁻¹ K⁻¹
- T
- absolute temperature K
Conditions and scope
- The dilute relation assumes an appropriate membrane and equilibrium temperature.
- Do not equate analytical formula-unit concentration with particle concentration without evaluating dissociation or association.
Sources · 1
References
Sources retain their recorded scope. A source link alone does not establish verification of every statement.
Evidence and review
Inspected dilute osmotic-pressure relation and van't Hoff particle-factor discussion.
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Entry details
Permanent link to this entry ↗- Record identity
- uni-chem-colligative-osmosis
- Revision
- core.1
- Structured reference record
- University core expansion