Chromatography and mass spectrometry

Question 1

the limitations of HPLC and GC are:

Answer 1

-though they are good at separating small quantities of components, they are not very good at positively identifying them:

• different components may have the same retention times
• it is also difficult to control all the variables (solvent, pressure and temperature)

Question 2

the names for the combination of mass spectrometry (MS) and HPLC and GC are:

Answer 2

HPLC-Ms

GC-MS

Question 3

the stages of identifying a component through GC-MS is:

Answer 3

the mixture is injected into a gas chromatograph

• each component has a different retention time, so emerges at a different time
• one at a time, each component enters the mass spectrometer
• the m/z value and relative abundances of components are compared with a database of known substances
• when a match is found, the substance s positively identified