What is meant by positive and negative deviations from Raoult's law and how is the sign of Delta H _(mix) related to positive and negative deviations from Raoult's law?

What is meant by positive and negative deviations from Raoult's law an

1.	What is meant by positive and negative deviations from Raoult's law and how is the sign of Delta H _(mix) related to positive and negative deviations from Raoult's law?
Answer» Solution :NEGATIVE deviations: In these type of deviations, the partial vapour pressure of each component A and B of solution is HIGHER than the vapour pressure calculated from Raoult.s law. For example: Water and ethanol, chloroform and water. POSITIVE deviations: In case of positive deviation A-B interactions are weaker than those between A-A or B-B. This means that in such solutions molecules or A (or B) will find it EASIER to positive deviation fromRaoult.s law.