Question

To separate a mixture of two or more miscible liquids for which the difference in boiling points is less than 25 K _______________ method is used. 
1. filtration
2. Separating funnel
3. fractional distillation
4. sublimation

Answer 1

Correct Answer - Option 3 : fractional distillation

separation of mixture:

• The process or methods of separation of different components of a mixture by the physical method is known as the separation of mixtures.

Fractional distillation

• Fractional distillation is a process that is used to refine petroleum, that is, separate the various components of petroleum. This is achieved based on the boiling points of each component.
• However, the difference in the boiling points of the materials should be less than 25°C from each other under a pressure of one atmosphere, for this process to be applied. 

Hence we can conclude that To separate a mixture of two or more miscible liquids for which the difference in boiling points is less than 25 K fractional distillation method is used. 

filtration:

• Filtration is the most common method of separating a liquid from an insoluble material.

Separating funnel:

• Separating funnel mostly used to separate two immiscible liquids.

sublimation:

• sublimation used to separate out sublime component.