Chapter 12 Nuclear Magnetic Resonance Spectroscopy
Multiple Choice
1. How many sets of equivalent hydrogen atoms are there for 2-propanol? (Sec. 12.6)
a)
b)
c)
d)
2
3
4
8
2. How many sets of equivalent hydrogen atoms are there for the following compound? (Sec. 12.6)
CH3
a)
b)
c)
d)
3
4
5
6
3. How many sets of signals are there in the 1H-NMR spectrum for 1,1-dichlorocyclohexane? (Sec. 12.6)
a)
b)
c)
d)
2
3
4
6
4. How many sets of signals are there in the 1H-NMR spectrum for diisopropyl ether? (Sec. 12.6)
a)
b)
c)
d)
1
2
3
6
5. How many sets of equivalent carbon atoms are there for the following compound? (Sec. 12.10)
CH3
OH
a)
b)
c)
d)
3
4
5
6
6. How many sets of equivalent carbon atoms are there for 1-bromo-3-chlorocyclohexane? (Sec. 12.10)
a)
b)
c)
d)
3
4
5
6
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Chapter 12 Nuclear Magnetic Resonance Spectroscopy
7. A compound gave two sets of signals in the 1H-NMR spectrum with an integration ratio of 60 to 10. Which is the most
likely structure for the compound? (Sec. 12.6, 12.7)
O
a) CH3CH2CH2CCH2CH2CH3
b) H3C
OH
CH3
O
H3C
CHCCH
d)
c) O
CH3
H3C
CH3
CH3
8. Which are the relative areas of integration in the 1H-NMR spectrum for 2-chloro-3-methylbutane? (Sec. 12.7)
a)
b)
c)
d)
9:1:1
3:3:3:1:1
6:3:2
6:3:1:1
9. Which is the order of increasing  values downfield from TMS for the methyl groups shown (lowest first)? (Sec. 12.8)
CH3 Br CH3 I CH3 OH CH3 F
I
a)
b)
c)
d)
II
III
IV
I, III, IV, II
II, I, III, IV
IV, II, III, I
III, IV, II, I
10. Which is the order in increasing chemical shift values in the 1H-NMR spectrum for the indicated hydrogen atoms (lowest
first)? (Sec. 12.8)
O
CH3 CH CH CH2 COH
I
a)
b)
c)
d)
II
III
IV
IV, II, III, I
I, III, II, IV
III, I, IV, II
II, IV, I, III
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Chapter 12 Nuclear Magnetic Resonance Spectroscopy
11. Which is the splitting pattern for the indicated hydrogen atom? (Sec. 12.9)
O
CH3
CH3COCH
CH3
a)
b)
c)
d)
septet
quartet
doublet
singlet
12. Which is the splitting pattern for the hydrogen atoms in 2,2-dibromopropane? (Sec. 12.9)
a)
b)
c)
d)
septet
quartet
doublet
singlet
13. The splitting pattern for a compound with molecular formula C3H5OCl gave a quartet and a triplet. Which is the most
likely structure for this compound? (Sec. 12.9)
O
a) CH3CCH2Cl
b) O
Cl
O
O
c) CH3CH2CCl
d) ClCH2CH2CH
14. Which compounds show signal splitting in the 1H-NMR spectrum? (Sec. 12.9)
CH3 O
O CH3
CH3COC CH3
CH3
CH3
CH3
C COCH2CH3
CH3O C CH3
CH3
I
CH3
III
II
a)
b)
c)
d)
OCH3
IV
I, II
III, IV
I, III
II, IV
15. Which compound has a singlet in the 1H-NMR at approximately 2.0 ppm and integrates to 3 hydrogens?
(Sec. 12.8, 12.9)
O
O
a) CH3CHOCH
CH3
b) CH3COCH2CH3
O
c) CH3CH2CH2OCH
O
d) CH3OCCH2CH3
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Chapter 12 Nuclear Magnetic Resonance Spectroscopy
16. Which compound has four sets of signals in the 1H-NMR spectrum? (Sec. 12.6)
O
O
a) CH3CHOCH
CH3
b) CH3COCH2CH3
O
c) CH3CH2CH2OCH
O
d) CH3OCCH2CH3
17. Which compounds have 3 signals in the 13C NMR spectrum? (Sec. 12.10)
HO
OH
OH
OH
OH
OH
OH
I
II
a)
b)
c)
d)
IV
III
I, II
I, II, III
I, III
I, II, III, IV
18. Which is the order of increasing  values in the 13C NMR spectra for the following carbon atoms? (Sec. 12.8)
CH4
I
a)
b)
c)
d)
CH3F
II
CH3Br
III
CH3OH
IV
CH3Cl
V
III, V, II, IV, I
I, IV, II, V, III
V, IV, II, III, I
I, III, V, IV, II
19. A compound has a single signal in the 13C NMR spectrum and a single signal in the 1H-NMR spectrum. Which is most
likely the compound? (Sec. 12.6, 12.10)
a)
b)
c)
d)
dimethyl ether
diethyl ether
2,2-dimethylpropane
methyl ethanoate
20. A compound has two signals in the 13C NMR spectrum and a single signal in the 1H-NMR spectrum. Which is most
likely the compound? (Sec. 12.6, 12.10)
a)
b)
c)
d)
dimethyl ether
diethyl ether
2,2-dimethylpropane
methyl ethanoate
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Chapter 12 Nuclear Magnetic Resonance Spectroscopy
21. A compound has three signals in the 13C NMR spectrum and two signals in the 1H-NMR spectrum. Which is most likely
the compound? (Sec. 12.6, 12.10)
a) bromobenzene
b) para dibromobenzene
c) ortho dibromobenzene
d) meta dibromobenzene
22. Which are the characteristic shift ranges for the indicated hydrogen atoms? (Sec. 12.8)
O
H3C
CCH2CH2CH3
H
I
III
IV
II
a)
b)
c)
d)
I = 0.8-1.0, II = 6.5-8.5, III = 2.2-2.5, IV = 2.1-2.3
I = 0.8-1.0, II = 2.2-2.5, III = 6.5-8.5, IV = 2.1-2.3
I = 2.2-2.5, II = 6.5-8.5, III = 0.8-1.0, IV = 2.1-2.3
I = 2.2-2.5, II = 6.5-8.5, III = 2.1-2.3, IV = 0.8-1.0
23. The compounds shown below can be distinguished by which 1H-NMR characteristics? (Sec. 12.11)
O
O
I) number of signals
II) splitting
III) integration
IV) chemical shift
a)
b)
c)
d)
I, II, IV
I, IV
II
IV
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Chapter 12 Nuclear Magnetic Resonance Spectroscopy
24. The compounds shown below can be distinguished by which 1H-NMR characteristics? (Sec. 12.11)
Cl
Cl
Cl
Cl
I) number of signals
II) splitting
III) integration
IV) chemical shift
a)
b)
c)
d)
I, II
I, IV
I, II
IV
25. The compounds shown below can be distinguished by which 1H-NMR characteristics? (Sec. 12.11)
O
O
O
I) number of signals
II) splitting
III) integration
IV) chemical shift
a)
b)
c)
d)
I, II, III
I, III, IV
I, II
IV
Fill in the Blank
1. The number of 1H signals for the following molecule is _____________. (Sec. 12.6)
O
O
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Chapter 12 Nuclear Magnetic Resonance Spectroscopy
2. The number of 1H signals for the following molecule is _____________. (Sec. 12.6)
CH3
CH3
3. The number of 1H signals for isopropyl ethyl ether is _____________. (Sec. 12.6)
4. The splitting of the three 1H signals of methyl propanoate are (left to right as drawn) _____, ______, ______. (Sec. 12.9)
O
O
5. The splitting of the three 1H signals of tetrahydropyran are (top to bottom as drawn) _____, ______, ______. (Sec. 12.9)
O
6. The integration of the 1H signal at 2.2 ppm for 3-pentanone is _________. (Sec. 12.7)
O
7. The integration of the 1H signal at 3.8 ppm for dipropyl ether is _________. (Sec. 12.7, 12.8)
8. The number of 13C signals for meta dimethoxybenzene is ________. (Sec. 12.10)
9. The expected chemical shift range (in ppm) for the indicated carbon of ethyl benzoate is ___________. (Sec. 12.10)
O
O
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Chapter 12 Nuclear Magnetic Resonance Spectroscopy
10. The expected chemical shift range (in ppm) for the indicated protons of E-2-pentene is ___________. (Sec. 12.8)
H
H
True-False
1. The number of 1H-NMR signals for propyl propanoate is 3. (Sec. 12.6)
O
O
2. The number of 1H-NMR signals for para methoxytoluene is 4. (Sec. 12.6)
3. The splitting of the signal for the indicated protons of 3-methylcyclohexanone is a quartet. (Sec. 12.9)
O
H
CH3
4. The splitting of the signal for the indicated protons of isopropyl formate is a septet. (Sec. 12.9)
CH3
O
H
O
H
CH3
5. The integration of the signal that includes the indicated protons of isopropyl formate is 3. (Sec. 12.7)
CH3
O
H
O
H
CH3
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Chapter 12 Nuclear Magnetic Resonance Spectroscopy
6. The integration of the signal that includes the indicated protons of meta hydroxybenzene is 2. (Sec. 12.7)
OH
OH
H
7. Ethyl 3-oxopentanoate has 5 proton signals and 5 carbon signals in the NMR spectra. (Sec. 12.6, 12.10)
O
O
O
8. 1,4-Cyclohexanedione has 2 proton signals and 4 carbon signals in the NMR spectra. (Sec. 12.6, 12.10)
O
O
9. A 1H-NMR shows a single signal and a 13C-NMR shows two signals. A possible structure for this compound is,
O
(Sec. 12.6, 12.10)
10. A 1H-NMR shows a single signal and a 13C-NMR shows two signals. A possible structure for this compound is,
O
(Sec. 12.6, 12.10)
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Chapter 12 Nuclear Magnetic Resonance Spectroscopy
Answers
Multiple Choice
1. b
2. d
3. b
4. b
5. c
6. d
7. d
8. d
9. b
10. b
11. a
12. d
13. c
14. d
15. b
16. c
17. d
18. d
19. a
20. c
21. c
22. d
23. d
24. b
25. b
Fill in the Blank
1. 4
2. 4
3. 4
4. t, q, s
5. t, q(5), q(5)
6. 4
7. 4
8. 5
9. 165-200 ppm
10. 5-5.7 ppm
True-False
1. F
2. T
3. F
4. T
5. F
6. T
7. F
8. F
9. T
10. T
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