3. A piece of chromatography paper was spotted with coloured inks obtained from pens labelled 1 to 6.
The diagram below shows the spots after the chromatogram was developed.
L
solvent front
1
2
3 4 5 6
Black Yellow Red Blue Green
Base line
(a) Which two pens contained the same pigment? (2 mark)
(b) Which pens contained only one pigment?
(2 mark)
(c) According to the chromatogram, which pigments are present in the ink of pen number 6. (2mks)
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