Explain how fractional distillation works.

In the given chromatogram, how can you tell that 'X' does not contain the substance 'C'?

Look at the chromatogram above. Can you think of a way to separate the coloured substances from the paper?

For the chromatogram above:

Were any of the amino acids in B-E also present in A? How can you tell at a glance? 

For the chromatogram above:

(solvent front travelled= $3.5$)

The amino acids travelled the distance from A-E is given, work out the ${\mathrm{R}}_{\mathrm{f}}$values for the amino acids in A-E.