Question

Write the principle and applications of the following methods of separation:

(a) Separating funnel

(b) Centrifugation

(c) Paper chromatography

Answer 1

• A separating funnel is a piece of laboratory glassware used in liquid-liquid extractions to separate the components of a mixture into two immiscible solvents phases of different densities. Oil and water can be separated by using a separating funnel.
• Centrifugation- Separating the suspended particles of a substance from a liquid in which the mixture is rotated at a high speed in a centrifuge.

The process of centrifugation is used in dairies to separate cream from milk.

• Chromatography-Separating two or more dissolved solids that are present in a solution in very small quantities. By using paper chromatography two or more different substances present in the same solution can be separated. Two or more substances may be soluble in the same solvent but their solubilities are different. Black ink, a mixture of several coloured substances, can be separated by this method.