23:Spectroscopy Flashcards
How does infra-red spectroscopy work
Molecules can absorb infra-red radiation and energy absorbed causes the covalent bonds in the molecules to vibrate.
What is fingerprinitng in spectroscopy
Comparing the compound’s vibrations with a spectral database to find an exact match
What is a molecular ion
The ion formed when an intact molecule simply loses one electron
What is the value of m/z for a molecular ion peak equal to
The Mr
Where does the m+1 peak come from
A small percentage (1.1%) of earth’s carbon atoms are ¹³C rather than ¹²C this means if a molecule contains one of these heavier carbon atoms, the molecule will have a mass one greater than normal
What is fragmentation
When larger molecules are bombarded with electrons (for mass spectrometry) parts can drop off, creating fragment ions
What are the uses of mass spectrometry
Detection of compounds,
Estimating the amounts of specific substances,
Detect and measure relative amounts of specific isotope (used in carbon dating)
