TO SEPARATE DIFFERENT COLOURS FROM GIVEN INK MIXTURE BY PAPER CHROMATOGRAPHY

MATERIAL REQUIREDS

Filter paper, beaker, beaker cover, dropper, mathematical box, distilled water, alcohol, given ink mixture

THEORY

Chromatography is a technique that is used for separating the components of a mixture by passing it through a column or sheet of an adsorbing material. The principle of this process depends upon the fact that “the different components of a mixture are adsorbed into different extents and move down the column at different rates.”It is of two types one is paper chromatography and another is absorbent chromatography.

Paper Chromatography: Chromatography technique that uses paper sheets or strips as the adsorbent being the stationary phase through which a solution is made to pass is called paper chromatography. It is an inexpensive method of separating dissolved chemical substances by their different migration rates across the sheets of paper.

The compounds in the mixture separate themselves based on the differences in their affinity towards stationary and mobile phase solvents under the capillary action of pores in the paper. Paper chromatography between solid and liquid phases, wherein the solid surface of the paper is the stationary phase and the liquid phase is the mobile phase.

PROCEDURE

• Take a filter paper then cut about 4 cm breadth and about 8 cm length.
• Draw two margin one about 5 mm height and another about 20 mm height along length labeled as A and B respectively.
• Keep small drop of given ink mixture at the center of margin B, then let to dry.
• Take a beaker with about 20 ml of 50% ethanol solution.
• Keep filter paper (which already prepared) inside beaker by dipping up to level A vertically without touching wall of beaker.
• Then cover beaker with glass plate and let up to 30 minutes.
• Then observe separated color band.

OBSERVATION

Different color band are seen in filter paper.

RESULT

…………….. color band separated from …….. Colour.

CONCLUSION

Hence different color can be separated from given ink mixture by paper chromatography.

PRECAUTION

• Do not use pure water should me mixed with alcohol or ammonia.
• Ink drop must be small.
• Do not dip ink drop mark to solvent.
• Filter paper should not attached with wall of beaker.
• Beaker must be covered.