Raoult's Law Calculator

Find a solution's vapor pressure.

Solution vapor pressure (kPa) 2.853

Formula: P = x_solvent × P°_solvent

Step-by-step with your numbers:

1. Values used:

2. Solvent mole fraction = 0.9

3. Pure solvent vapor pressure = 3.17 kPa

5. Solution vapor pressure = Solvent mole fraction x Pure solvent vapor pressure = 0.9 x 3.17 = 2.853kPa

Did we solve your problem today?

Raoult's law gives the vapor pressure of an ideal solution.

The math behind it

P = solvent mole fraction × pure-solvent vapor pressure. A non-volatile solute lowers vapor pressure.

x 0.9, P° 3.17 kPa → 2.85 kPa.

Two volatile components?

Add each component's partial pressure (x × P° each).