Question

Why paper strip with a spot of ink at it's end is dipped into the solvent

Answer 1

Dear student

The end of the paper, nearest the spot, is dipped into the solvent without submerging the spot itself because

In ascending chromatography, the solvent is in a pool at the bottom and moves up by capillarity. The solvent flows along the paper through the spots and on, carrying the substances from the spot. Each of these will, if the solvent mixture has been well chosen, move at a different rate from the others. After a time the paper is taken out and dried: the substances can be seen at once if coloured, or located by treating with a suitable locating agent. In this way, we can separate the components of ink.

Regards