Question 1

How many peaks would you expect in the proton decoupled 13C NMR spectrum of 3-bromopentane?

Accepted Answer

A)   1
B)   2
C)   3
D)   4
E)   5F) B) and C)
G) A) and C)

Question 2

The proton(s)  on which C will produce a splitting pattern that is a doublet in its 1H NMR spectrum? 1H NMR spectrum?   A)  1 B)  2 C)  3 D)  4 E)  5" class="answers-bank-image d-inline" rel="preload" >

Accepted Answer

A)   1
B)   2
C)   3
D)   4
E)   5F) B) and E)
G) A) and E)

Question 3

Which of the following molecules has more than three (3)  different types of protons in its 1H NMR? 1H NMR?   A)  I B)  II C)  III D)  IV E)  V" class="answers-bank-image d-inline" rel="preload" >

Accepted Answer

A)   I
B)   II
C)   III
D)   IV
E)   VF) B) and E)
G) A) and C)

Question 4

Which of the following compounds is most likely to absorb ultraviolet radiation in the range of 200 to 400 nm?

Accepted Answer

A)   
B)   
C)   
D)   
E)   F) A) and E)
G) A) and B)

Question 5

An IR spectrum of an unknown organic molecule having the molecular formula of C4H8O shows no absorptions at 1630-1780 cm-1 or at 3200-3500 cm-1.To what class of compounds does the unknown belong?

Accepted Answer

A)   alcohol
B)   carboxylic acid
C)   ketone
D)   ether
E)   aldehydeF) All of the above
G) B) and E)

Question 6

A hydrocarbon shows a parent ion peak in its mass spectrum at m/z 102.Its 1H NMR spectrum shows only two peaks, a singlet at  δ \delta δ  2.7 (1H)  and a multiplet at  δ \delta δ  7.4 (5H) .The correct structure is:

Accepted Answer

A)   1H NMR spectrum shows only two peaks, a singlet at   \delta   2.7 (1H)  and a multiplet at   \delta   7.4 (5H) .The correct structure is: 
A)     
B)     
C)     
D)     
E)     " class="answers-bank-image d-inline" rel="preload" >
B)   1H NMR spectrum shows only two peaks, a singlet at   \delta   2.7 (1H)  and a multiplet at   \delta   7.4 (5H) .The correct structure is: 
A)     
B)     
C)     
D)     
E)     " class="answers-bank-image d-inline" rel="preload" >
C)   1H NMR spectrum shows only two peaks, a singlet at   \delta   2.7 (1H)  and a multiplet at   \delta   7.4 (5H) .The correct structure is: 
A)     
B)     
C)     
D)     
E)     " class="answers-bank-image d-inline" rel="preload" >
D)   1H NMR spectrum shows only two peaks, a singlet at   \delta   2.7 (1H)  and a multiplet at   \delta   7.4 (5H) .The correct structure is: 
A)     
B)     
C)     
D)     
E)     " class="answers-bank-image d-inline" rel="preload" >
E)   1H NMR spectrum shows only two peaks, a singlet at   \delta   2.7 (1H)  and a multiplet at   \delta   7.4 (5H) .The correct structure is: 
A)     
B)     
C)     
D)     
E)     " class="answers-bank-image d-inline" rel="preload" > F) A) and B)
G) B) and E)

Question 7

Bending vibrations in the infared region occur at:

Accepted Answer

A)   3000 cm-1
B)   2200 cm-1
C)   1700 cm-1
D)   below 1400 cm-1
E)   over 3000 cm-1F) C) and D)
G) None of the above

Question 8

A compound C3H3Cl5 has a 1H NMR spectrum that consists of a triplet at  δ \delta δ  4.5 and a doublet at  δ \delta δ  6.0 (J = 7 Hz)  with relative areas 1:2.Its structure is

Accepted Answer

A)   CH3CCl2CCl3
B)   CH2ClCCl2CHCl2
C)   CHCl2CCl2CCH2Cl
D)   CHCl2CHClCHCl2
E)   CH2ClCHClCCl3 F) A) and B)
G) A) and C)

Question 9

The following compound will have an 1H NMR spectrum that consists of: 1H NMR spectrum that consists of:   A)  two singlets, area ratio 6:4. B)  three singlets, area ratio 3:3:4. C)  four singlets, area ratio 3:3:2:2. D)  two singlets and two doublets, area ratio 3:3:2:2. E)  two triplets and a singlet, area ratio 3:3:4." class="answers-bank-image d-inline" rel="preload" >

Accepted Answer

A)   two singlets, area ratio 6:4.
B)   three singlets, area ratio 3:3:4.
C)   four singlets, area ratio 3:3:2:2.
D)   two singlets and two doublets, area ratio 3:3:2:2.
E)   two triplets and a singlet, area ratio 3:3:4.F) A) and C)
G) D) and E) D

Question 10

Which of following will have three peaks in its 1H decoupled 13C NMR spectrum?

Accepted Answer

A)   pentane
B)   isopentane
C)   isobutane
D)   benzene
E)   m-chlorotolueneF) None of the above
G) B) and D)

Question 11

Which of the following compounds will have one peak in its 1H NMR and two peaks in its 13C NMR spectrum?

Accepted Answer

A)   1H NMR and two peaks in its 13C NMR spectrum? 
A)     
B)     
C)     
D)     
E)    " class="answers-bank-image d-inline" rel="preload" >
B)   1H NMR and two peaks in its 13C NMR spectrum? 
A)     
B)     
C)     
D)     
E)    " class="answers-bank-image d-inline" rel="preload" >
C)   1H NMR and two peaks in its 13C NMR spectrum? 
A)     
B)     
C)     
D)     
E)    " class="answers-bank-image d-inline" rel="preload" >
D)   1H NMR and two peaks in its 13C NMR spectrum? 
A)     
B)     
C)     
D)     
E)    " class="answers-bank-image d-inline" rel="preload" >
E)   1H NMR and two peaks in its 13C NMR spectrum? 
A)     
B)     
C)     
D)     
E)    " class="answers-bank-image d-inline" rel="preload" >F) B) and E)
G) B) and C)

Question 12

The following compound will have a proton NMR spectrum that shows:

Accepted Answer

A)   two singlets, area ratio 3:1.
B)   two singlets, area ratio 9:1.
C)   three singlets, area ratio 3:3:6.
D)   four singlets, area ratio 3:2:6:1.
E)   six singlets, area ratio 3:3:3:1:1:1.F) A) and B)
G) A) and C)

Question 13

Which bond would show a strong, broad absorption in the IR between 3600 and 3200 cm-1?

Accepted Answer

A)   O-H
B)   C-Cl
C)   C=O
D)   C-H
E)   C-OF) A) and B)
G) D) and E)

Question 14

Compounds that will show only two sharp singlets in their 1H NMR spectra are: 1H NMR spectra are:   A)  1 and 2 B)  3 C)  1 and 3 D)  1 and 4 E)  1, 2, and 4" class="answers-bank-image d-inline" rel="preload" >

Accepted Answer

A)   1 and 2
B)   3
C)   1 and 3
D)   1 and 4
E)   1, 2, and 4F) B) and C)
G) A) and E)

Question 15

Which of the following molecules will show two peaks with an area ratio of 6:4 in its 1H NMR spectrum? 1H NMR spectrum?   A)  I B)  II C)  III D)  IV E)  V" class="answers-bank-image d-inline" rel="preload" >

Accepted Answer

A)   I
B)   II
C)   III
D)   IV
E)   VF) C) and D)
G) A) and E)

Question 16

In the 1H NMR spectrum of the following molecule, the protons on which carbon will have the most downfield chemical shift? 1H NMR spectrum of the following molecule, the protons on which carbon will have the most downfield chemical shift?   A)  1 B)  2 C)  3 D)  4 E)  5" class="answers-bank-image d-inline" rel="preload" >

Accepted Answer

A)   1
B)   2
C)   3
D)   4
E)   5F) A) and B)
G) B) and E)

Question 17

As the wavelength of the radiation decreases, the increases.

Accepted Answer

A)   energy
B)   frequency
C)   wave number
D)   all of these
E)   all decreaseF) D) and E)
G) A) and B) D

Question 18

Which of the following molecules would absorb at the longest wavelength in the ultraviolet region?

Accepted Answer

A)   hexane
B)   2-hexene
C)   2,4-hexadiene
D)   1,3,5-hexatriene
E)   cyclohexaneF) None of the above
G) C) and E)

Question 19

Which molecule will produce two lines in the proton decoupled 13C NMR spectrum?

Accepted Answer

A)   CH3CH2OH
B)   CH3OCH3
C)   CH3CH2CH2OH
D)   CH3OCH2CH3
E)   13C NMR spectrum? 
A)   CH3CH2OH 
B)   CH3OCH3 
C)   CH3CH2CH2OH 
D)   CH3OCH2CH3 
E)    " class="answers-bank-image d-inline" rel="preload" >F) B) and C)
G) D) and E)

Question 20

The area in the infared spectrum between 1400 and 400 cm-1 is called the .

Accepted Answer

A)   solid region
B)   fingerprint region
C)   functional group region
D)   location region
E)   none of theseF) A) and E)
G) B) and D) B

Exam 12: Spectroscopy and Structure Determination

How many peaks would you expect in the proton decoupled 13C NMR spectrum of 3-bromopentane?

Correct AnswerverifiedShow Answer

The proton(s) on which C will produce a splitting pattern that is a doublet in its 1H NMR spectrum?

Correct AnswerverifiedShow Answer

Which of the following molecules has more than three (3) different types of protons in its 1H NMR?

Correct AnswerverifiedShow Answer

Which of the following compounds is most likely to absorb ultraviolet radiation in the range of 200 to 400 nm?

Correct AnswerverifiedShow Answer

An IR spectrum of an unknown organic molecule having the molecular formula of C4H8O shows no absorptions at 1630-1780 cm-1 or at 3200-3500 cm-1.To what class of compounds does the unknown belong?

Correct AnswerverifiedShow Answer

A hydrocarbon shows a parent ion peak in its mass spectrum at m/z 102.Its 1H NMR spectrum shows only two peaks, a singlet at δ \delta δ 2.7 (1H) and a multiplet at δ \delta δ 7.4 (5H) .The correct structure is:

Correct AnswerverifiedShow Answer

Bending vibrations in the infared region occur at:

Correct AnswerverifiedShow Answer

A compound C3H3Cl5 has a 1H NMR spectrum that consists of a triplet at δ \delta δ 4.5 and a doublet at δ \delta δ 6.0 (J = 7 Hz) with relative areas 1:2.Its structure is

Correct AnswerverifiedShow Answer

The following compound will have an 1H NMR spectrum that consists of:

Correct AnswerverifiedD

Which of following will have three peaks in its 1H decoupled 13C NMR spectrum?

Correct AnswerverifiedShow Answer

Which of the following compounds will have one peak in its 1H NMR and two peaks in its 13C NMR spectrum?

Correct AnswerverifiedShow Answer

The following compound will have a proton NMR spectrum that shows:

Correct AnswerverifiedShow Answer

Which bond would show a strong, broad absorption in the IR between 3600 and 3200 cm-1?

Correct AnswerverifiedShow Answer

Compounds that will show only two sharp singlets in their 1H NMR spectra are:

Correct AnswerverifiedShow Answer

Which of the following molecules will show two peaks with an area ratio of 6:4 in its 1H NMR spectrum?

Correct AnswerverifiedShow Answer

In the 1H NMR spectrum of the following molecule, the protons on which carbon will have the most downfield chemical shift?

Correct AnswerverifiedShow Answer

As the wavelength of the radiation decreases, the increases.

Correct AnswerverifiedD

Which of the following molecules would absorb at the longest wavelength in the ultraviolet region?

Correct AnswerverifiedShow Answer

Which molecule will produce two lines in the proton decoupled 13C NMR spectrum?

Correct AnswerverifiedShow Answer

The area in the infared spectrum between 1400 and 400 cm-1 is called the .

Correct AnswerverifiedB

How many peaks would you expect in the proton decoupled ¹³C NMR spectrum of 3-bromopentane?

Correct Answer
verified

The proton(s) on which C will produce a splitting pattern that is a doublet in its ¹H NMR spectrum?

Correct Answer
verified

Which of the following molecules has more than three (3) different types of protons in its ¹H NMR?

Correct Answer
verified

Correct Answer
verified

An IR spectrum of an unknown organic molecule having the molecular formula of C₄H₈O shows no absorptions at 1630-1780 cm^-¹ or at 3200-3500 cm^-¹.To what class of compounds does the unknown belong?

Correct Answer
verified

A hydrocarbon shows a parent ion peak in its mass spectrum at m/z 102.Its ¹H NMR spectrum shows only two peaks, a singlet at $\delta$ 2.7 (1H) and a multiplet at $\delta$ 7.4 (5H) .The correct structure is:

Correct Answer
verified

Correct Answer
verified

A compound C₃H₃Cl₅ has a ¹H NMR spectrum that consists of a triplet at $\delta$ 4.5 and a doublet at $\delta$ 6.0 (J = 7 Hz) with relative areas 1:2.Its structure is

Correct Answer
verified

The following compound will have an ¹H NMR spectrum that consists of:

Correct Answer
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D

Which of following will have three peaks in its ¹H decoupled ¹³C NMR spectrum?

Correct Answer
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Which of the following compounds will have one peak in its ¹H NMR and two peaks in its ¹³C NMR spectrum?

Correct Answer
verified

Correct Answer
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Which bond would show a strong, broad absorption in the IR between 3600 and 3200 cm^-¹?

Correct Answer
verified

Compounds that will show only two sharp singlets in their ¹H NMR spectra are:

Correct Answer
verified

Which of the following molecules will show two peaks with an area ratio of 6:4 in its ¹H NMR spectrum?

Correct Answer
verified

In the ¹H NMR spectrum of the following molecule, the protons on which carbon will have the most downfield chemical shift?

Correct Answer
verified

Correct Answer
verified
D

Correct Answer
verified

Which molecule will produce two lines in the proton decoupled ¹³C NMR spectrum?

Correct Answer
verified

The area in the infared spectrum between 1400 and 400 cm^-¹ is called the .

Correct Answer
verified
B