Medicine: Spectroscopy ( Mass / IR ) Flashcards
What does an infrared spectrometer record
Frequencies absorbed by molecules
What is the units of frequency for a IR spec
Wavenumber , cm^-1
Definition of the fingerprint region on an IR spec
Anything below 1500cm^-1
What is special about the peak of an O-H ( alcohol ) molecule on an IR spec
It is always broad not sharp
What happens to a molecule in a mass spectrometer
A molecule becomes a +ve ion when an electron is knocked out of the outer shell of one of its atoms
What is the name given to a molecule when it becomes a +ve ion as a result of an electron being knocked out of the outer shell of one of its atoms
Molecular ion
What is the m/z value of a molecular ion
The same as the Mr of the molecule the ion is made from
Definition of fragments
Result of molecules breaking up into smaller parts
Fragments dah also become ionised
How are fragments shown on a mass spec
Each fragment produces a peak in the mass spectrum of the compound
What kind of peak does the molecular ion produce and why
The peak with the greatest m/z value as this is the unbroken molecule
What is the biggest peak on mass spec called and what does it show
Base peak = produced by the most abundant ion
What is a slight exception in the mass spec
A small peak at M+ +1 caused by the presence of a C13 isotope
