Question

What is the important criterion to use chromatography for separating components of a mixture?

Answer 1

Chromatography is a separation based on different polarity of the solvents. Here different compound come from stationary phase the out at a specific time

Complete step by step answer:
Chromatography is the method of separation, purification, and testing of compounds. The word chromatography means colour-writing. It consists of two phases: stationary phase and the mobile phase. The analyte is mixed with suitable liquid or gaseous mobile phase and is allowed to move through the column. Mostly one phase is hydrophilic and the other is hydrophobic. The analyte interacts with both the phases in different manner depending on the polarity. Thus, separation of mixture into its constituents takes place based on its interaction with the phases. Each sample elute from the stationary phase at a specific time. This is then passed through the detector and the obtained signal is plotted as a chromatogram.
The major classification of chromatography based on different properties of compounds in stationary and mobile phase
A. Paper chromatography
Here filter paper is used as a stationary phase the mixture to be separated is applied on it. The mobile phase is a suitable solvent.
B. Column chromatography
Here a column is used as a stationary phase the mixture to be separated is mixed with suitable mobile phase and fed to the column.
C. Thin layer chromatography
Here a thin coating of aluminium oxide or silica gel on a glass slide or plastic sheet is used as stationary phase the mixture to be separated is mixed with suitable mobile phase and spotted on the plate
Chromatography can be quantitatively found by the retention factor.
${{\text{R}}_{\text{f}}}\,{\text{ = }}\,\dfrac{{{\text{distance}}\,{\text{travelled}}\,{\text{by}}\,{\text{component}}}}{{{\text{distance}}\,{\text{travelled by solvent front}}}}$
Therefore, the important criterion to use chromatography for separating components of a mixture is the difference in solubility of the liquids.

Note: In a Column chromatography eluent is the fluid entering the column eluate is fluid that comes out through the column and elution is the process of washing out a compound through a column using a suitable solvent.

Components of a solution nonvolatile solid solute and a liquid solvent and mixtures of liquids with different boiling points can be separated by distillation.