GC002 GC definitions - Part 1

 

Elution: The process in which a mobile phase is continuously passed through or along the chromatographic bed and the sample is fed to the system as a finite slug.

Chromatographic processes names are linked to the state of the mobile phase. Hence, the mobile phase is a gas in GC and a liquid in LC.

In GC, the sample is vaporized and carried through the column by the carrier gas. The components of the sample equilibrate into and out the stationary liquid phase in the column. These equilibriums are dependent on temperature and the components separate from one another based on their affinities for the stationary phase and relative vapor pressures.

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