Osmotic Pressure
| Formula / Notation | Π = MRT (van't Hoff); Π = cRT for ideal dilute solution |
|---|---|
| Also Known As | Osmotic pressure, Π, van't Hoff osmotic pressure, turgor pressure (biological) |
What is Osmotic Pressure?
The pressure that must be applied to a solution to prevent osmosis through a semi-permeable membrane. Given by π = MRT (van't Hoff equation), where M is molar concentration and T is temperature. Used to measure molar mass of large molecules and in water purification (reverse osmosis).
Formula & Notation
Other Names / Synonyms: Osmotic pressure, Π, van't Hoff osmotic pressure, turgor pressure (biological)
Properties & Characteristics
Uses & Applications
Safety Information
Always consult the SDS/MSDS before handling any chemical. This information is for educational purposes only.
Key Facts
Frequently Asked Questions
The pressure that must be applied to a solution to prevent osmosis through a semi-permeable membrane. Given by π = MRT (van't Hoff equation), where M is molar concentration and T is temperature. Used to measure molar mass of large molecules and in water purification (reverse osmosis).
Osmotic pressure is applied in: desalination (reverse osmosis, where pressure exceeding Π forces water through membrane against osmosis), pharmaceutical IV solution design (isotonic solutions at 0.9% NaCl or 5% glucose to match blood osmotic pressure), membrane osmometry (measuring polymer molar mas…
Intravenous solutions must be carefully isotonic: hypotonic solutions cause red blood cell lysis (haemolysis); hypertonic solutions cause crenation (cell shrinkage). Rapid shifts in plasma osmolality (hypernatraemia correction too fast) can cause dangerous central pontine myelinolysis. Reverse osmos…
The formula or notation for Osmotic Pressure is: Π = MRT (van't Hoff); Π = cRT for ideal dilute solution