How does the boiling point affect gas chromatography?
The more involatile the substance, the longer should be its retention time on a gas chromatograph.
Gas chromatography is akin to fractional distillation, in which the more volatile components of a mixture are collected first. As analyte is introduced onto the column, the analyte is forced down the column with a flow of inert carrier gas. The more volatile (i.e. the lower boiling point!) the component, the less time it should spend on the column, and the lesser the retention time. More volatile components thus should appear on the chromatograph first.