Explain the principle and technique of column chromatography.
Answers
It is the technique use for separation of those solutes that dissolve in some solvent in very small quantities but there solubility may be different.It can be used to separate dye from ink. The method for separation is as follows--
• Take a thin and long strip of filter paper. Draw a pencil line on it about 3 cm from one end.
• Put a small drop of black ink on it at centre of pencil line.
• When the drop of ink has dried, the filter paper strip should vertically dip in water but the pencil line should remain above water level.
• When the water reaches the top end, the strip is removed from jar and dried.
• Separate coloured spots is obtained at paper strip.
APPLICATION OF CHROMATOGRAPHY
• To separate colours from dye.
• Pigments from natural colour.
• Drugs from blood.
The basic principle involved in column chromatography is to adsorb solutes of the solution with the help of a stationary phase and further separating the mixture into discrete components.