Question

Chromatography technique is used for the separation of:
A) Small sample of mixture
B) Plant pigments
C) Dye stuffs
D) All of the above

Answer 1

Hint: Of all the analytical methods known for separation, chromatographic methods are the most efficient methods for separation of substances. Recall the applications of paper chromatography technique. It is used for separating and identifying mixtures that are coloured.

Complete answer:
Chromatography technique can be defined as a physical method of separation of mixtures. It is brought about by the dynamic partitions or distribution of dissolved materials between two immiscible phases, one of which is called the mobile phase, and the other is called the stationary phase. One phase stays in place while the other moves through it. The phase which stays in place is known as the stationary phase and the phase which moves through the system (a column, plate, capillary tube or sheet) is known as mobile phase. The mobile phase can be a liquid or a gas whereas the stationary phase can be a liquid or a solid.

Some uses of chromatography:
Chromatography not only rules among the separation methods of chemicals but is also applied to qualitative and quantitative analysis of the separated species.
- Paper chromatography is the simplest and most inexpensive form of chromatography. It is often used for separating and identifying mixtures that are coloured or can be coloured. It is a useful technique for the separation and identification of different plant pigments. It is also used to separate mixtures of dye stuff (since they are coloured).
Therefore, chromatography technique is used for the separation of small samples of mixture, plant pigments as well as dye stuff. Thus, option D is correct.

Note:
Chromatography was invented and named by the Russian botanist Mikhail Tswett in 1900. He developed the technique primarily to separate various plant pigments such as chlorophyll and xanthophylls.