Paper chromatography

This kit enables to test paper chromatography. All chromatographic techniques consist of a system with a stationary phase and a mobile phase that cannot be mixed with each other. The mobile phase flows over the stationary one. Other substances included in the system may be: 1. retained completely by the stationary phase, 2. conveyed completely by the mobile phase, 3. partially retained and partially conveyed. In the last case there is a competition between stationary and mobile phases. In fact the final result consists in modifying the rate at which the substance crosses the system. Different substances will have different rates and they will cross the system in different times. There are three types of chromatographic techniques:

– Thin Layer Chromatography (TLC) where the thin layer (stationary phase) is applied onto a sheet

– Paper chromatography (similar to TLC) where paper is used as stationary phase

– Column chromatography where the stationary phase is included in a pipe.

This kit uses paper chromatography to separate the constituents of a pigment.