Chromatography: Separation of coloured liquids.
Chromatography is used to separate mixtures of coloured compounds. The colours are separated out according to the speed the particles travel using a suitable solvent.
Solvents: if you are using water soluble ink from felt tip pens then water is a suitable solvent. If you are using permanent markers or Sharpies, you will need to use ethanol or propyl alcohol because these inks are not water soluble.
To make a Chromatogram:
Take a piece of filter paper, draw a pencil line across the bottom, about 3cms from the edge, and trim off the bottom.
Put ink blobs on the pencil line. Curl the paper and secure it together with a paper clip
Put about 1.5 cm of water (or ethanol) in a beaker. Stand your paper in the solvent and watch as the inks rise!
In this example, 3 different inks were place on the pencil line and the paper was placed in a beaker with water. As the water was absorbed by the filter paper the inks separated out into the colours which make them.
In this example a blob of black ink was placed in the center of the filter paper. Water was slowly dropped onto the blob and the ink then separated into the colours which make it.