To determine which mixture shows positive deviation from Raoult's law, we need to understand the concept of Raoult's law and deviations.$\\$Raoult's law states that the partial vapor pressure of each component in an ideal solution is directly proportional to its mole fraction.$\\$Positive deviation from Raoult's law occurs when the interactions between the different components of the mixture are weaker than the interactions in the pure components. This results in a higher vapor pressure than expected.$\\$Let's analyze each option:$\\$• Benzene + Toluene: Both are non-polar hydrocarbons with similar structures, leading to ideal behavior with no significant deviation.$\\$• Acetone + Chloroform: This mixture shows negative deviation because of strong hydrogen bonding between acetone and chloroform molecules.$\\$• Chloroethane + Bromoethane: Both are similar halogenated hydrocarbons, likely to behave ideally with no significant deviation.$\\$• Ethanol + Acetone: Ethanol is capable of hydrogen bonding, while acetone is a polar aprotic solvent. The interaction between ethanol and acetone is weaker than the hydrogen bonding in pure ethanol, leading to positive deviation.$\\$Therefore, the mixture that shows positive deviation from Raoult's law is Ethanol + Acetone. This corresponds to Option 4.