Definition of Chromatography

Chromatograhy may be defined as a methos of separating a mixture of components into individual components through equilibrium distribution between two phases.

Essentially, the technique of chromatography  is based on the differences in the rate at which the components of a mixture move through a porous medium (called stationary phase) under the influence of some solvent or gas (called moving phase).

  The chromatographic method of separation, in general , involves the following steps:
1. Adsorption or retention of a substance or substances on the stationary phase.
2. Separation of the adsorbed substances by the mobile phase.
3. Recovery of the separated substances by a continuous flow of the mobile phase, the method being called elution.
4. Qualitative and quantitative analysis of the eluted substances.