Extraction involves the separation of a solid from a solution mixture by selective precipitation.
A separatory funnel is the commonly used instrument for extraction. In it, two liquid layers are used for the selective precipitation of a solid from the liquid phase based on difference in density and solubility.
The most common form of an extraction is an acid-base extraction, which uses the different acidities of compounds to selectively precipitate one compound over another.
Concept: Acid-Base Extraction9m