For purification of solids following methods are employed
Crystallization:-In this process compound is dissolved in
suitable solvent and this saturated solution of impure
substance is filtered through the funnel. The filterate
which is hot is now allowed to stand undisturbed, with the
result crystals deposits are found. These crystals can be
than washed on porcelain funnel of Buckner type
Sublimation:-Certain compounds on heating pass directly from
solid into gases and on cooling is the gases these at once
form solids e.g. naphthalene campor etc..
Purification of liquids:-There are number of methods for
this which are as follows:
(a)Simple Distillation:-In this process, vaporisation and
crystallization go in side by side
(b)Distillation under reduced pressure:-When heated to B.P.,
organic compounds get decomposed e.g. glycerine. These
substances can be purified by these processes
(c)Stem Distillation :-Liquids which possess high vapour
pressure e.g. aniline is purified by this method
Chromatography:-This is based on differential absorption of
the different constituents of mixture on varions absorbent
e.g. magnesium oxide, silica gel etc.
THE PURIFICATION OF THE ORGANIC COMPOUNDS CAN BE DONE BY
SEVERAL WAY SUCH AS COLOUMN CHROMATOGRAPHY,
RECRASTALISATION BY USING THE SUITABLE SOLVENT,
DISTILLATION, FILLTRAION,WASHING. PURIFICATION MAY DEPENDS
ON THE NATURE OF COMPOUND AND THE INMPURITY IN IT.
organic compounds can be purified by physical as well as chemical methods:
some of them are: crystallization,fractional crystallization,sublimation,separation of two liquids using separating funnel,simple distillation,fractional distillation( it should be noted that fractional distillation of compounds liquids mixture is possible only if they do not form a constant boiling azeotrope mixture,distillation,steam distillation,extraction with a solvent,azeotropic distillation,chromatography
chromatography may be classified as gas chromatography and liquid chromatography.