Chromatography__

Our topic for today is Chromatography.
Does black ink consist of only black color or any other color as well?
Let us find out by the process of paper chromatography.
Chromatography is a technique of separating two or more dissolved solids which are present in a solution in very small quantities.
Take a strip of filter paper.
Draw a line with a pencil close to the lower edge of the paper.
Put a small drop of ink on the center of the line.
Let it dry for sometime.
Take a jar containing some water.
Put the filter paper in it such that the drop of ink is just above the water level.
After sometime, the water starts gradually rising up by capillary action.
As the water moves up, it takes the dyes present in the ink along with it.
Slowly, we start seeing some different colors on the paper as the water rises up, these are the different dyes present in the ink.
Different dyes have different solubility levels and travel at different speeds as the water rises up.
As a result, we see different colors at different heights and the dyes get separated.
Hence, in this way paper chromatography is used to separate the different colors in a dye.