What are the different phases of column chromatography?

Column chromatography consists of the solid phase and the mobile phase. The solid phase absorbs and separates the compounds passing through it with the assistance of a liquid mobile phase. The stationary phase is a solid material packed inside a column. The choice of stationary phase depends on the nature of the sample and the goal of the separation. The polarity of the sample plays a crucial role in determining whether the analyte spends more or less time in the stationary phase and if they experience slower or faster movement through the column. The stationary phase remains fixed in place and acts as a constraint on the substances in a mixture. It slows them down to move slower than the mobile phase.

The mobile phase flows through the column. The sample being separated is injected at the beginning of the column and moves throughout the system by the mobile phase. Different substances disperse according to their affinity for the two phases. The higher the solubility in the mobile phase, the faster the molecule will disperse through the column. The movement of substances in the mobile phase is regulated by the processes in their interactions with the mobile and/or stationary phases. Due to their differences in factors of specific components of the mobile phase and their affinity for the solid phase, some substances will move faster than others. Each sample elutes from the stationary phase at a specific time known as retention time. As the analytes pass through the detector, their signal is recorded and plotted on a chromatogram.