A solution shows **positive deviation** from Raoult's law when:
AA–B interactions are weaker than A–A and B–B
BThe solution obeys Raoult's law exactly
CA–B interactions are stronger than A–A and B–B
DThe solute dissociates completely
Answer & Solution
Correct answer: A. A–B interactions are weaker than A–A and B–B
**Positive deviation**: weaker A–B forces → molecules escape more easily → **higher VP than Raoult predicts**. Δ_mix H > 0 and Δ_mix V > 0. Example: ethanol + acetone (acetone breaks ethanol H-bonds).
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