According to Raoult's Law:

1. Ideal Solutions: Mixtures where solute-solute and solvent-solvent interactions are similar to solute-solvent interactions obey Raoult's law. Examples include Benzene + Toluene and Chloroethane + Bromoethane.
2. Negative Deviation: Occurs when intermolecular attractive forces between the solute and solvent (A-B) are stronger than those in pure components. Acetone + Chloroform shows negative deviation because chloroform forms hydrogen bonds with acetone molecules.
3. Positive Deviation: Occurs when A-B interactions are weaker than A-A and B-B interactions. In Ethanol + Acetone, pure ethanol molecules are held together by strong hydrogen bonds. Adding acetone disrupts these bonds, weakening the overall intermolecular forces and leading to a higher vapour pressure than predicted (Positive Deviation).