Theory

Gas Chromatography is an analytical seperation technique used to analyze volatile substances in the gas phase. With Chromatography in it's name that means there must be two phases within this method, the Mobile and Stationary Phase. The Mobile Phase is prepared by first dissolving and vaporizing the analyte and mixing it with a Carrier, an inert gas like Helium and/or Nitrogen, which brings it through a heated column. The Stationary Phase is either microscopic film of liquid of solid depending on the situation and analyte. These are termed as gas-solid Chromatography (GSC) or gas-liquid chromatography (GLC)

Gas Chromatography is also known for being one of the sole forms of chromatogrphy that has no need for the mobile phase reacting with the analyte. Further more the seperation also depends on the chemical affinity of the stationary phase.

PROCESS

The Carrier Gas is pumped through the column
- The Carrier Gas is a gas that is inert/unreactive meaning that it won't react when the vaporized analyte is being injected.
The sample is injected and volatilize
- This is where the sample is vaporize or volatilized into the appropriate analyte. The GC will not be able to annalyze the sample if it is not volatile or even if it's semi-volatile.
Sample Speparation is based on vapor pressure and solubility of the stationary phase.
Carrier Gas and Analyte generate a signal in the detector.
The signal is amplified and the chromatogram is produced.