The solution formed by adding carbon disulphide to acetone, shows positive deviation from Raoult's law. It is because

Carbon disulphide and acetone shows positive deviation from Rault's law because carbon disulphide and acetone interactions are weaker than carbon disulphide-carbon disulphide and acetone- acetone interactions, Hence molecules of CS2 or acetone will escapes easily. Hence vapour pressure increases which results in positive deviation.Minimum boiling azeotrope is formed by CS2 and acetone mixture.