Explain, why an organic liquid vaporises at a temperature below its boiling point in its steam distillation?
In steam distillation, the organic liquid starts to boil when the sum of vapour pressure due to the organic liquid(p2) and the vapour pressure due to water(p1) becomes equal to the atmospheric pressure(p), that is, p=p1+p2
Since,p1>p2,organic liquid will vapourise at a lower temperature than its boiling point.