Question

Please answer the following questions about the Thin-Layer Chromatography

The principle of TLC (mobile/stationary phase)

How/why do compounds separate on a TLC plate?

Answer 1

Thin Layer Chromatography is a separation technique which is used to separate non-volatile compounds.

The stationary phase is usually a glass plate covered with silica gel, while the mobile phase is a solvent which rises up the thin layer of stationary phase through capillary action.

A small spot of sample mixture is applied on the bottom of the plate, and when the solvent rises upwards the components of the mixture come in contact with the solvent and interact with it, and thus they rise at different speeds with the mobile phase, which causes them to separate as different bands.