gas chromatography

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gas chromatography An analytical technique in which the components of a sample are separated by partitioning between either a mobile gas and a thin layer of non-volatile liquid held on a solid support (gas–liquid chromatography) or between the gas and a solid absorbent as the stationary phase (gas–solid chromatography). Partitioning occurs repeatedly throughout the column, and, as each solute travels at its own rate, a band corresponding to each solute will form. Solutes are eluted (washed out) in increasing order of partition ratio, and enter a detector attached to the column exit. The time of emergence of a peak on the display identifies a component, and the area under each peak is proportional to the component's concentration. Gas chromatography is used mainly in the analysis of volatile organic compounds.

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