Chromatography is a technique used to separate mixtures of substances that are soluble in the same solvent. A spot of the mixture is placed on filter paper and a solvent is used to carry the different substances along the paper at different rates, based on how strongly they interact with the solvent and paper. This allows the different substances to be visually identified based on how far they travel up the paper compared to samples of single known substances run alongside the mixture.

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Chromatography
Chromatography means colour-writing.
Chromatography is used to separate mixtures of coloured or
non-coloured substances that are soluble in the same solvent.
A spot of the mixture is placed on some filter paper.
In method B, the solvent is
slowly dripped onto the paper.
In method A, the solvent
is soaked up the paper.

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Chromatography experiment

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Identifying dyes in a mixture
Which dyes does the mixture contain?
Dots of single dyes are placed alongside a dot of unknown
mixture.
The solvent washes up the paper, and then the pattern of the
dyes in the mixture can be compared with the single dyes.

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Which dyes?

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Which separation technique?

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Separating mixtures