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
Answer:
A 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.
A mixture of two miscible liquids having a difference in their boiling points more than 25 °C can be separated by the method of simple distillation.
The boiling point of kerosene = around 150–180 °C
The boiling point of petrol = 95 °C
Procedure:
In this method, the mixture of kerosene and petrol is taken in a distillation flask with a thermometer fitted in it also consider a beaker, water condenser, and a Bunsen burner. The mixture is heated slowly, since the boiling point of petrol is less compare to kerosene, it will first undergo vaporization and condense in the water condenser. The condensed petrol is collected from the condenser outlet, whereas kerosene is left behind in the distillation flask.