Question

During fractional distillation of petroleum, different fractions are obtained. Its name, number of atoms of carbon, the temperature range at which it is obtained and its use are given. There is an error in one of the alternatives. In which alternative there is an error?
(a)Petrol, ${{C}_{5}}\text{ }to\text{ }{{C}_{10}},\text{ }303k\text{ }to\text{ }393K,$fuel in vehicles
(b)Diesel, ${{C}_{15}}\text{ }to\text{ }{{C}_{18}},\text{ }533k\text{ }to\text{ }613K,$fuel in vehicles and generators
(c)Naphtha, ${{C}_{8}}\text{ }to\text{ }{{C}_{10}},\text{ }393k\text{ }to\text{ }453K,$solvent in petrochemicals
(d)Lubricating oil, ${{C}_{8}}\text{ }to\text{ }{{C}_{12}},\text{ }400K,$fuel in high speed vehicles

Answer 1

Hint: A method of distillation that requires the separation of miscible liquids is fractional distillation. Repeated distillations and condensations are involved in the process, and the mixture is typically divided into component sections.

Complete answer:
Fractional distillation is the separation of a mixture into sections, or fractions of its component. Separate chemical compounds by heating them to a temperature at which one or more parts of the mixture vaporise. It is used for fractionation distillation.
Distillation can result in significantly complete separation, or a partial separation can result in an increase in the concentration of chosen components in the blend.
Lubricating oil, ${{C}_{16}}\text{ }\text{ }to\text{ }{{C}_{20}}\text{ }\text{ }above\text{ }613K$ is used in machine lubrication oil and for the preparation of grease, vaseline etc.
So,
Option (d) lubricating oil,${{C}_{8}}\text{ }\text{ }to\text{ }{{C}_{12}}\text{ }~400~K~$fuel in high speed vehicles is the right answer.
So, the correct answer is “Option D”.

Note: In general, the component parts have boiling points which differ under one atmosphere pressure from each other by less than $25~{}^\circ ~C~\left( 45~{}^\circ ~F \right).$Usually a simple distillation is used when the difference in boiling points is greater than $25~{}^\circ ~C.$
The basic principle of this kind of distillation is that various liquids boil at different temperatures and evaporate. Thus, when the mixture is heated, the substance with lower boiling point begins first to boil and transform into vapours.