Indifference curve described

Azeotropes What we have discussed so far in this section is only valid for mixtures of components that behave indifferently toward each other in both their liquid and vapor states. However, the hquid state often exhibits differing behavior. If the two components are highly compatible, the stronger interaction of the particles in the liquid mixture relative to the pure state hinders the transition to the vapor phase. The partial pressures of the components are smaller than in the case of indifferent behavior and the vapor pressure curves show a negative deviation from Raoult s law. Compared to the behavior of indifferent substances, the curves appear more or less distorted. As long as the disturbance is small, the behavior can be described in a similar manner as before. 

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