What is the principle involved in the separation of a mixture by chromatography? - Leaving Cert Chemistry - Question j - 2011

The principle involved in chromatography is based on the selective adsorption of components in a mixture. Each component has different affinities for the stationary phase and the mobile phase, which leads to their separation. The components partition between these two phases due to their varying interactions with them.

In more detail, chromatography exploits the differences in the distribution of substances between a stationary phase and a mobile phase. The components of a mixture move at different rates through the stationary phase as they interact with it and the mobile phase, causing them to separate over time.