Question

two liquids a and b on mixing forms a warm solution.what type of deviation does it show from raoults law

Answer 1

Since warm solution, means heat is liberated, so ∆H = -ve.

Hence, negative deviation.

Answer 2

On mixing A and B , the solution becomes warm.

This means heat released in formation of new bonds between A and B molecules is more than the heat absorbed for the breaking of molecules of A and B .

Therefore , the vapour pressure of the solution is reduced and thus the mixture shows negative deviation from Roult's law .