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What is chromatography?
 Chromatography is a group of laboratory techniques to separate the components of a mixture by passing the mixture through a stationary phase.
Chromatography is a process that can be used to isolate the various components of a mixture. There are a number of different types in use, including gas, liquid, paper, and gel permeation chromatography.
The process relies on the fact that different molecules will behave in different ways when they are dissolved in a solvent and moved across an absorbent medium.
Example TLC: Thin Layer Chromatography.

This technique involves the use of an inert piece of glass, plastic or metal. It is a simple and inexpensive technique used to judge the purity of a synthesized compound. It is also used to detect the extent of progress of a particular chemical reaction. A drop of solution to be analyzed is added to the TLC glass plate, which has already been coated with a thin layer of silica gel. This silica coated glass plate acts as the stationary phase. The sheet is then placed in a glass chamber containing a solvent, which forms the mobile phase. Via capillary action, the solvent moves upwards and carries the molecules of the solution to be detected at different rates. The components of the solution will appear in the form of a series of spots at various locations on the plate. Calculations are made based on ratio of the distance that the substance travels to the distance that the solvent travels up the plate.


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