Chromatography is the technique for the separation, purification, and testing of compounds.
In this process, we apply the mixture to be separated on a stationary phase (solid or liquid) and a pure solvent such as water or any gas is allowed to move slowly over the stationary phase, carrying the components separately as per their solubility in the pure solvent.
Example: It is used to separate the coloured components (dyes) in black ink.