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Discuss three modes of Paper Chromatography

Discuss three modes of Paper Chromatography

Answers

Faith
1. Ascending chromatography: As the name indicates, the chromatogram ascends. Here, the development of paper occurs due to the solvent movement or upward travel on the paper.
The solvent reservoir is at the bottom of the beaker. The paper tip with sample spots just dips into the solvent at the bottom so that spots remain well above the solvent.
2. Descending chromatography: Here, the development of paper occurs due to solvent travel downwards on the paper. The solvent reservoir is at the top. The movement of the solvent is assisted by gravity besides the capillary action. 3. Ascending- descending mode: Here solvent first travels upwards and then downwards on the paper.
4. Radial mode: Here, the solvent moves from the center (mid-point) towards the periphery of circular chromatography paper. The entire system is kept in a covered Petri dish for the development of the chromatogram.
The wick at the center of paper dips into the mobile phase in a petri dish, by which the solvent drains on to the paper and moves the sample radially to form the sample spots of different compounds as concentric rings.
5. Two-dimensional chromatography: Here the chromatogram development occurs in two directions at right angles.
In this mode, the samples are spotted to one corner of rectangular paper and allowed for first development. Then the paper is again immersed in the mobile phase at a right angle to the previous development for the second chromatogram.
Titany answered the question on September 13, 2021 at 06:41

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