Chapter 20

Describe the principles of gas chromatography.

What are the main types of gas chromatography?

Compare packed and capillary columns in number of plates.

Describe the principles of the following gas chromatography detectors: (a) thermal conductivity, (b) flame ionization, (c) electron capture.

Gas reduction valves used on gas tanks in gas chromatography usually give the pressure in psig (pounds per square inch above atmospheric pressure). Given that atmospheric pressure (760 torr) is 14.7 psi, calculate the inlet pressure to the gas chromatograph in torr, for 40.0 psig, if the ambient pressure is 745 torr.

Using Chemical Abstracts or SciFinder Scholar (the online access to Chemical Abstracts - see Appendix \(\mathrm{A}\) ) if your library subscribes to it, find at least one article on the gas chromatography determination of ethanol in blood. Read the journal article and write a summary of the principle of the method and prepare a synopsis of the procedure used including any sample preparation. Is there information on the accuracy and precision of the method?