what is osmotic pressure

Osmotic pressure is the minimum pressure required to stop the flow of solvent molecules through a semipermeable membrane from a dilute solution to a concentrated solution.

It occurs due to the process of osmosis.

Simple explanation

When two solutions of different concentrations are separated by a semipermeable membrane, water moves from the dilute solution to the concentrated solution. The pressure needed to stop this movement is called osmotic pressure.

Important points

• Represented by the symbol: π

• Depends on:

  • Concentration of solution

  • Temperature

  • Number of solute particles

Example

Plant roots absorb water from the soil due to osmotic pressure.

Importance of osmotic pressure

• Helps in water absorption in plants

• Maintains fluid balance in living cells

• Important in medical solutions like saline drips

Osmotic pressure is an important concept in biology, chemistry, and medicine.