Discuss the behaviour of non-ideal solution having negative deviations from Raoult's law.

Explanation

In these solutions, magnitude of forces of interaction increases on mixing the two components of the solution. A------B interactions are more than that A ------A and B-----B interactions.
Partial vapour pressure of each component and total pressure of solution will be less as compared to an ideal solution. `p_(A)gtp_(A)^(@)x_(A),p_(B)gtp_(B)^(@)x_(B)`.
These solutions have following characteristics :
(i) `DeltaV_("mixing")` is negative.
Molecular forces of intraction increasee. Molecules of two components come closer. Thus, volume of the solution decreases.
(ii) `DeltaH_("mixing")` is negative. Process of mixing is exothermic in nature. Energy is released due to increased forces of interactions. For solid solute, solubility decreases with increase in temperature.
Examples of non-ideal solutions
(i) Acetone and chloroform. (ii) Acetone and aniline.