Define Descending type of paper chromatography?
In descending chromatography, the movement or flow of mobile phase is in downward direction. In this technique the solvent is kept in a trough at the top of chamber and then allowed to flow down the paper. The movement of the liquid is caused by capillary action, as well as, by gravitational pull.
The rate of flow of mobile phase is more rapid in this case as compared to that in ascending development. The basic material of the paper use for chromatography is a cellulose of high purity, which is present in 98.99 %. This paper is composed of randomly directed cellulose fibers. The cellulose itself is a network of long chains of carbohydrate with molecular weight of more than 1,00,000 possessing hydrophilic.