Fractional condensation is a laboratory technique used to separate the components of a vapor containing a mixture of substances. This is done by taking advantage of the fact that the different chemicals have different boiling points. The mixture undergoes repeated condensations, where the chemical with the highest boiling point condenses out of the vapor first and can be separated from the rest, then the chemical with the next highest boiling point condenses out, etc.
From the BioTech Dictionary at http://biotech.icmb.utexas.edu/. For further information see the BioTech homenode.
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