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Usefulness of chromatography
is used to separate different colored substances in a mixture in
order to determine its composition.
Chromatography of a mint syrup: preparation
need to prepare the chromatography paper:
- The chromatography paper can be simply realized with a retangle of
- A line must be drawn at about 1 cm from the bottom (using a pencil
because ink can contain dyes that could disrupt chromatography): it
is the origin line.
- A drop of mint syrup is deposited with a pipette on the origin line.
We then prepare the chromatography tank:
- This can be a simple beaker.
- Some water is poured ( about one centimeter ).
3) Realization of chromatography
chromatography paper must be suspended in the tank and must soak in
water without wetting the origin line.
Through capillary action, the water is sucked through the filter paper
and rises (such as coffee that rises in a sugar).
The rising water brings with it the drop
of mint syrup from which are
separated a yellow dye and a blue dye.
experiment shows that the green dye from mint syrup is actually a
mixture of two colors: a yellow dye and blue dye.
Principle of chromatography
that rises in the chromatography paper brings with it a blue and a
yellow dyes, but yellow dye moves slowlier than blue, they
therefore separate and form two distinct spots.
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