Free interactive chemistry · GUIDE-RAOULT
Raoult’s law and vapour pressure
Solvent molecules escape from the surface as vapour. Adding a solute, or a second liquid, changes the vapour pressure.
Open the interactive simulation →How to use this simulation
- Choose “Solute in solvent” or “Two liquids”.
- Choose the solvent or mixture.
- Move the mole-fraction slider and wait for “Equilibrium”.
- Compare the measured pressure with Raoult’s law on the graph.
What to notice
- Solute particles take up part of the surface, so fewer solvent molecules escape.
- Real mixtures deviate from Raoult’s law and can form azeotropes.
Try this
Find a mixture with an azeotrope. Why can’t distillation separate it?
Try it for free →