Question

Explain as to why non-ideal solutions deviate from Raoult’s law.

Answer 1

Non-ideal solutions deviate from Raoult’s law because the intermolecular forces between solute and solvent molecules are either stronger or weaker than those present in the pure components. If the solute–solvent interactions are weaker, the vapour pressure increases (positive deviation), and if they are stronger, the vapour pressure decreases (negative deviation).