How will you separate a mixture containing kerosene and petrol (difference in their boiling points is more than 25°C), which are miscible with each other?
Answers
technique known as simple distillation can be used to separate the mixture of miscible liquids, where the difference in boiling point is more than 25°C, to name a few – kerosene and petrol. The whole concept is established on the volatility property of substances. The following are the various steps in the process of simple distillation:
(a) In a distillation flask, take the mixture.
(b) Treat the mixture with heat while a thermometer is affix.
(c) We observe evaporation of petrol as it has a low boiling point.
(d) As the vapours advance towards the condenser, a dip in the temperature causes condensation of the vapours into liquid which can be accumulated in a flask.
(e) We notice that kerosene tends to remain in the flask in a liquid state due to comparatively higher boiling point.
(f) Consequently, the liquids are separated.
We can separate a mixture containing kerosene and petrol by simple distillation because kerosene and petrol do not decompose on heating and their boiling points are sufficiently apart.The apparatus used for the simple distillation is given in the attachment.