Show:
IR Spectroscopy
H-1 NMR Spectroscopy
C-13 NMR Spectroscopy
Mass Spectroscopy
Pot luck
100
Absorption of IR radiation causes molecules to move to higher levels of what type of energy?
Vibrational
100
What does NMR stand for?
Nuclear Magnetic Resonance
100
What units are used to describe chemical shifts in NMR spectroscopy?
ppm
100
A mass spectrometer separates ions based on what property?
mass/charge ratio
100
What is another name for H-1 NMR?
proton NMR
200
What region of the IR spectrum is unique to every compound?
Fingerprint region
200
NMR spectroscopy uses electromagnetic radiation in what frequency range?
radio
200
What is the name of the reference compound used in NMR spectroscopy?
TMS (tetramethylsilane)
200
Why do so many different peaks appear on a mass spectrum from the analysis of a single compound?
ionisation causes fragmentation of the compound, resulting in fragment ions of various masses
200
What type of atoms have 'spin'?
atoms containing a nucleus that has an odd number of either protons or neutrons
300
What term describes the values represented on the x axis of an IR spectrum?
Wavenumbers
300
A triplet splitting pattern indicates how many neighbouring hydrogens?
2
300
What information does the number of peaks in C-13 NMR spectra tell us?
The number of different carbon environments
300
Which peak on a mass spectrum is referred to as the base peak?
The one showing the highest intensity/abundance
300
What effect does symmetry have on the number of different hydrogen or carbon environments in a molecule?
Symmetrical molecules have fewer different hydrogen and carbon environments
400
The fingerprint region of the IR spectrum includes bands that fall within what range of frequencies?
500 - 1400 cm-1
400
What information does peak area tell us about a compound?
The proportion of hydrogen atoms in each environment
400
How many peaks would appear on a spectrum produced from C-13 NMR spectroscopy of ethyl ethanoate
4
400
What useful information can be gained by observing the position of the molecular ion peak?
relative molecular mass
400
Which of these techniques (IR spectroscopy, H-1 NMR spectroscopy, C-13 NMR spectroscopy or mass spectrometry) does not use electromagnetic radiation?
mass spectrometry
500
What characteristic bond causes an absorbance band at 1670 - 1750 cm-1
C=O
500
How many hydrogen environments are present in butanone?
3
500
Why is signal splitting not seen in C-13 NMR?
Because of the low abundance of C-13 isotopes, it is unlikely that C-13 atoms will be adjacent to each other
500
What effect does the presence of bromine or chlorine atoms in a compound have on the mass spectrum produced?
Multiple molecular ion peaks. As the number of atoms with significant proportions of isotopes increases, the mass spectrum becomes more complex.
500
Which is your favourite spectroscopic technique out of IR spectroscopy, H-1 NMR spectroscopy, C-13 NMR spectroscopy or mass spectrometry?
Correct!