Question

Explain the method of fractional distillation

Answer 1

Fractional distillation is a method used to separate a mixture of liquid by making use of their different boiling point. The liquid mixture passed through a chamber and converted into vapour, the vapour condenses at different stages thus separating liquid.

Crude oil is separated in this way.

Hope it helps ^_^ 

Answer 2

Fractional distillation :- if the boiling points of the two liquid of the mixture are very close to one to another .i.e differ by 10K or so, the separation can't be achieved by the simple distillation , then we use fractional distillation .

reason , why mixture of two is not seprated by simple distillation ,??
★ at the boiling point of the more volatile liquid of the mixture there will be sufficient vapour of the less volatile liquid as well , as a result , both of the liquids of the mixture will distill together and the separation is denied .

method of fractional distillation /
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in fractional is used distillation various type of fractionating column .shown in figure .

Procedure :- suppose we have a mixture of two liquid A and B of which A is more volatile then B , when such a liquid mixture is heated , the temperature rises slowly and mixture starts boiling .the vapours formed mainly consist of more volatile liquid A with little of less volaltile liquid B . As these vapours travel up the fractionating column , the vapours of less voltile liquid B condense more readily then liquid A . therefore the vapour rising up becomes richer in A and liquid flowing down becomes richer in B .

this process of distillation and condensations is repeated at every point in the fractionating column . As a result of series of successive distillation , by the time the vapour reach the top of the column and escape into the condenser .