gas chromatography, gc
DESCRIPTION
Gas Chromatography, GC. L.O.: Explain the term: retention time . Interpret gas chromatograms in terms of retention times and the approximate proportions of the components of a mixture. Explain that analysis by gas chromatography has limitations. - PowerPoint PPT PresentationTRANSCRIPT
Gas Chromatography, GC
L.O.:
Explain the term: retention time.
Interpret gas chromatograms in terms of retention times and the approximate proportions of the components of a mixture.
Explain that analysis by gas chromatography has limitations
After watching this clip, answer the following questions:
1)What is Gas chromatography (GC) used for?Separate volatile components in a mixture.2) What is the stationary phase? Liquid or solid3) What is the mobile phase?Inert gas4) What is retention time?In gas chromatography is the time for a
component to pass from the column inlet to the detector.
Limitations of GC: Many chemicals may have the same
retention time.Not all the samples may be separated.
Unknown compound have no reference retention time for comparison.
GC-MSL.O.:
Explain that mass spectrometry can be combined with gas chromatography in GC–MS to provide a far more powerful analytical tool than gas chromatography alone.
Explain that the mass spectra generated can be analysed or compared with spectral databases for positive identification of a component.
• State the use of GC–MS in analysis in forensics, environmental analysis, airport security and space probes
Homework
1) Do a PowerPoint explaining a use of GC-MS (1-2 slides).
2)Upload the PowerPoint into the HW section of the wiki (you will need to request membership first). Save as “yourname-GCMS”.
3) Prepare to do a 1 minute presentation using your PowerPoint
GC-MS
The separated components are directed into a mass spectrometer.
The generated mass spectrum is unique and definitive for a single compound.