Mihsaba
العربيةEnglishEspañolFrançais
Mihsaba›Chemistry›Osmotic Pressure Calculator

Osmotic Pressure Calculator

Calculate osmotic pressure from molarity, temperature and van’t Hoff factor using Π=iMRT, with atm, kPa and mmHg outputs.

The van’t Hoff equation is an ideal dilute-solution approximation; concentrated or real electrolyte solutions may require activity/osmotic corrections.

How to use

The van’t Hoff relation describes ideal osmotic pressure for a dilute solution as proportional to effective particle count, molarity and absolute temperature.

  1. Enter molarity in mol/L.
  2. Enter temperature in °C.
  3. Enter van’t Hoff factor i.
  4. Review pressure in several units.

How it is calculated

Π=iMRT

Example

For a 0.1 M solution at 25°C with i=1, ideal osmotic pressure is about 2.45 atm.

Important notes

This is an ideal relation; concentrated or real electrolyte solutions can deviate because interactions and incomplete dissociation change the effective particle count.

Frequently asked questions

What is i?

The van’t Hoff factor approximates the effective number of dissolved particles produced per formula unit.

Why convert to Kelvin?

Gas-like thermodynamic relations use absolute temperature.

Can I use concentrated solutions?

Only as a rough ideal estimate; activity or osmotic-coefficient corrections may be needed.