Chem 233 Questions and Answers
Electrospray ionization is a soft ionization technique. (1 pts) - answer True
Which of the following electrospray ionization mass spectra corresponds to a compound
that contains one chlorine atom? (1 pts) - answer 3:1 ratio
Which of the following electrospray ionization mass spectra corresponds to a compound
that contains one bromine atom? - answer 1:1 ratio
Which of the following electrospray ionization mass spectra corresponds to a molecule
with a neutral molecular weight of 102 g/mol? - answer 125 (102+23)
A non-polar bond will always show a signal in an IR spectrum. - answer False
Increasing the mass of atoms connected by a bond results in the absorbance of a
higher wavenumber of light. - answer 1
Select the bond that would absorb the highest wavenumber of light in an IR experiment.
- answer C-N Triple bond
Which of the following wavenumber ranges corresponds to the fingerprint region in an
IR spectrum? (2 pts) - answer <1500 cm-1
Which of the following structures would you expect to have a carbonyl stretch above
1700 cm-1 in an IR spectrum? Select all that apply. (2 pts) - answer carbocyclic acid,
ester, aldehyde, ketone
Which of the following IR stretches would be consistent with the C-H bond in the below
structure where the carbon is sp hybridized? - answer 3300 cm-1
Which of the following stretches would NOT be present in an IR spectrum of the below
compound? Select all that apply. (3 pts) - answer 3400 cm-1, 3300 cm-1, 2100 cm-1
(3100cm-1= sp2 C-H, 2950cm-1= sp3 C-H, 1700cm-1= c=o, 1650cm-1= c=c)
Based on the peaks you see in the following IR spectrum, what types of bonds are
present in this unknown compound? Select all that apply. - answer -OH, C=O, Csp3-
H
Electrospray ionization is a soft ionization technique. (1 pts) - answer True
Which of the following electrospray ionization mass spectra corresponds to a compound
that contains one chlorine atom? (1 pts) - answer 3:1 ratio
Which of the following electrospray ionization mass spectra corresponds to a compound
that contains one bromine atom? - answer 1:1 ratio
Which of the following electrospray ionization mass spectra corresponds to a molecule
with a neutral molecular weight of 102 g/mol? - answer 125 (102+23)
A non-polar bond will always show a signal in an IR spectrum. - answer False
Increasing the mass of atoms connected by a bond results in the absorbance of a
higher wavenumber of light. - answer 1
Select the bond that would absorb the highest wavenumber of light in an IR experiment.
- answer C-N Triple bond
Which of the following wavenumber ranges corresponds to the fingerprint region in an
IR spectrum? (2 pts) - answer <1500 cm-1
Which of the following structures would you expect to have a carbonyl stretch above
1700 cm-1 in an IR spectrum? Select all that apply. (2 pts) - answer carbocyclic acid,
ester, aldehyde, ketone
Which of the following IR stretches would be consistent with the C-H bond in the below
structure where the carbon is sp hybridized? - answer 3300 cm-1
Which of the following stretches would NOT be present in an IR spectrum of the below
compound? Select all that apply. (3 pts) - answer 3400 cm-1, 3300 cm-1, 2100 cm-1
(3100cm-1= sp2 C-H, 2950cm-1= sp3 C-H, 1700cm-1= c=o, 1650cm-1= c=c)
Based on the peaks you see in the following IR spectrum, what types of bonds are
present in this unknown compound? Select all that apply. - answer -OH, C=O, Csp3-
H
