Notes
Rf Values
Content of the notes (1)
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Rf Values
Chromatography
can be used to separate mixtures of coloured compounds – mixtures that are
suitable for separation by chromatography include inks, dyes and colouring
agents in food…
Simple
chromatography is carried out on paper – a spot of the mixture is placed near
the bottom of a piece of chromatography paper and the paper is then placed
upright in a suitable solvent.
Simple
chromatography is carried out on paper – a spot of the mixture is placed near
the bottom of a piece of chromatography paper and the paper is then placed
upright in a suitable solvent.
Different
chromatograms and the separated components of the mixtures can be identified by
calculating the Rf
value
Rf = distance
moved by the compound ÷ distance
moved by the solvent
The
Rf value of a particular compound is
always the same – if the chromatography has been carried out in the same way.
This
allows industry to use chromatography to identify compounds in mixtures
(precisely).
