Test Bank Docx Chapter 9 NMR & Mass Spectrometry Tools

Package Title: Solomons Test Bank

Course Title: Solomons 13e

Chapter Number: 9

Question type: Multiple Choice

1) How many signals would you expect to find in the ¹H NMR spectrum of CH₃OCH₂CH₂OCH₃?

A) 1

B) 2

C) 3

D) 4

E) 5

Topic: Proton NMR- Chemical Shift, Splitting, Etc.

Section: 9.2

Difficulty Level: Easy

2) Predict the splitting pattern you would observe for the proton at C1 of 2,3-dimethyl-2-phenylbutane.

A) Doublet

B) Singlet

C) Quartet

D) Septet

E) Octet

Topic: Proton NMR- Chemical Shift, Splitting, Etc.

Section: 9.2

Difficulty Level: Easy

3) Which one of the following best represents the predicted approximate chemical shift and coupling for the hydrogen(s) indicated with the arrow?

A) 1.10 ppm, singlet

B) 2.10 ppm, doublet

C) 3.40 ppm, singlet

D) 4.5 ppm, singlet

E) 3.5 ppm, quartet

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Easy

4) Which one of the following best represents the predicted approximate chemical shift and coupling for the hydrogen(s) indicated with the arrow?

A) 1.00 ppm, singlet

B) 2.10 ppm, singlet

C) 2.10 ppm, quartet

D) 3.00 ppm, singlet

E) 2.10 ppm, triplet

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Easy

5) Which one of the following best represents the predicted approximate chemical shift and coupling for the hydrogen(s) indicated with the arrow?

A) 1.00 ppm, quartet

B) 2.40 ppm, singlet

C) 2.40 ppm, quartet

D) 3.00 ppm, quartet

E) 2.40 ppm, triplet

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Easy

6) Which one of the following best represents the predicted approximate chemical shift and coupling for the hydrogen(s) indicated with the arrow?

A) 1.00 ppm, quartet

B) 2.40 ppm, singlet

C) 2.40 ppm, quartet

D) 3.00 ppm, quartet

E) 1.00 ppm, triplet

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Easy

7) Which one of the following best represents the predicted approximate chemical shift and coupling for the hydrogen(s) indicated with the arrow in the compound nicotine?

A) 6.00 ppm, singlet

B) 5.00 ppm. doublet

C) 7.00 ppm, multiplet

D) 9.00 ppm, triplet

E) none of these choices

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Easy

8) Which one of the following best represents the predicted approximate chemical shift and coupling for the hydrogen(s) indicated with the arrow in the compound nicotine?

A) 1.00 ppm, triplet

B) 2.00 ppm, doublet

C) 5.00 ppm, triplet

D) 7.00 ppm. mulitplet

E) None of these choices.

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Easy

9) Which one of the following best represents the predicted approximate chemical shift and coupling for the hydrogen(s) indicated with the arrow in the compound nicotine?

A) 1.00 ppm, singlet

B) 2.00 ppm, doublet

C) 3.00 ppm, broad multiplet

D) 5.00 ppm, broad multiplet

E) None of these choices.

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Easy

10) Which one of the following best represents the predicted approximate chemical shift and coupling for the hydrogen(s) indicated with the arrow?

A) 5.40 ppm, multiplet

B) 2.00 ppm, multiplet

C) 2.00 ppm, doublet

D) 2.00 ppm, quartet

E) 5.40 ppm, doublet

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Easy

11) Which one of the following best represents the predicted approximate chemical shift and coupling for the hydrogen(s) indicated with the arrow?

A) 5.40 ppm, doublet

B) 1.00 ppm, multiplet

C) 2.00 ppm, doublet

D) 1.00 ppm, doublet

E) 5.40 ppm, multiplet

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Easy

12) Which one of the following best represents the predicted approximate chemical shift and coupling for the hydrogen(s) indicated with the arrow?

A) 3.00 ppm, doublet

B) 3.00 ppm, triplet

C) 5.00 ppm, triplet

D) 1.00 ppm, doublet

E) 5.40 ppm, multiplet

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Easy

13) Which one of the following best represents the predicted approximate chemical shift and coupling for the hydrogen(s) indicated with the arrow?

A) 3.00 ppm, doublet

B) 3.00 ppm, triplet

C) 5.00 ppm, triplet

D) 1.00 ppm, doublet

E) 3.00 ppm, singlet

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Easy

14) For the following compound how many different signals would you see in the proton NMR? (Assume that you can see them all.)

A) 4

B) 5

C) 6

D) 7

E) 8

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Easy

15) For the compound dimedone, how many different signals would you see in the proton NMR? (Assume that you can see them all.)

A) 2

B) 3

C) 4

D) 5

E) None of these choices.

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Easy

16) For the following compound how many different signals would you see in the proton NMR? (Assume that you can see them all.)

A) 4

B) 5

C) 6

D) 7

E) 8

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Easy

17) For the following compound how many different signals would you see in the proton NMR? (Assume that you can see them all.)

A) 1

B) 2

C) 3

D) 4

E) 5

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Easy

18) For the compound adamantine, how many different signals would you see in the proton NMR? (Assume that you can see them all.)

A) 1

B) 2

C) 3

D) 4

E) None of these choices.

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Easy

19) A downfield ( 9-10) singlet is observed in the ¹H NMR spectrum of:

A)

B)

C)

D)

E)

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Easy

20) For the following compound how many different signals would you see in the proton NMR? (Assume that you can see them all.)

A) 1

B) 2

C) 3

D) 4

E) 5

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Medium

21) For the following compound how many different signals would you see in the proton NMR? (Assume that you can see them all.)

A) 4

B) 5

C) 6

D) 7

E) 8

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Medium

22) Which one of the following best represents the predicted approximate chemical shift and coupling for the hydrogen(s) indicated with the arrow?

A) 1.10 ppm, singlet

B) 2.10 ppm, triplet

C) 3.40 ppm, triplet

D) 4.5 ppm, singlet

E) 5.3 ppm, doublet

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Medium

23) Predict the splitting pattern you would observe for the proton at C4 of 2,3-dimethyl-2-phenylbutane.

A) Doublet

B) Singlet

C) Quartet

D) Septet

E) Octet

Topic: Proton NMR- Chemical Shift, Splitting, Etc.

Section: 9.2

Difficulty Level: Medium

24) How many ¹H NMR signals would trans-1,2-dichlorocyclopropane give?

A) 1

B) 2

C) 3

D) 4

E) 5

Topic: Proton NMR- Chemical Shift, Splitting, Etc.

Section: 9.2

Difficulty Level: Medium

25) How many chemically distinct ¹H NMR signals are there in the following compound?

A) 1

B) 2

C) 3

D) 4

E) 5

Topic: Proton NMR- Chemical Shift, Splitting, Etc.

Section: 9.2

Difficulty Level: Medium

26) How many ¹H NMR signals would cis-1,2-dichlorocyclopropane give?

A) 1

B) 2

C) 3

D) 4

E) 5

Topic: Proton NMR- Chemical Shift, Splitting, Etc.

Section: 9.2

Difficulty Level: Medium

27) How many ¹H NMR signals would you expect from this compound?

A) 1

B) 2

C) 3

D) 4

E) 5

Topic: Proton NMR- Chemical Shift, Splitting, Etc.

Section: 9.2

Difficulty Level: Medium

28) The ¹H NMR spectrum of which of these compounds would consist of a triplet, singlet and quartet only?

A) 2-chloro-4-methylpentane

B) 3-chloro-2-methylpentane

C) 3-chloropentane

D) 1-chloro-2,2-dimethylbutane

E) 3-chloro-3-methylpentane

Topic: Proton NMR- Chemical Shift, Splitting, Etc.

Section: 9.2

Difficulty Level: Medium

29) Which one of the following best represents the predicted approximate chemical shift and coupling for the hydrogen(s) indicated with the arrow?

A) 1.00 ppm, doublet

B) 2.00 ppm, singlet

C) 2.00 ppm, triplet

D) 2.00 ppm, doublet

E) 1.00 ppm, triplet

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Medium

30) Which of the following compounds would not be represented by a lone singlet in the proton NMR?

A) cyclohexane

B) benzene

C) dimethyl ether (CH₃-O-CH₃)

D) 1,2-ethanediol

E) none of these choices

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Medium

31) A compound C₅H₁₁Cl which exhibits only two singlets in the ¹H NMR spectrum must be:

A) 1-Chloropentane

B) 1-Chloro-2,2-dimethylpropane

C) 1-Chloro-2-methylbutane

D) 3-Chloropentane

E) 1-Chloro-3-methylbutane

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Medium

32) A compound that would show two triplets and a septet in the ¹H NMR spectrum could be:

A) 3-ethylpentane

B) 2-bromopropane

C) chlorocyclopropane

D) 1-iodopropane

E) none of these choices

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Medium

33) Consider the expected ¹H NMR spectrum of 1,1,3,3-tetramethylcyclopentane. Which of the following is likely to be observed?

A) 7 signals: all singlets

B) 7 signals: 4 singlets, 3 doublets

C) 3 signals: all singlets

D) 3 signals: one singlet, 2 doublets

E) 3 signals: two singlets, one doublet

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Medium

34) Consider the expected ¹H NMR spectrum of 2,4-dimethyl-1,4-pentadiene. Which of the following is likely to be observed?

A) 7 signals: all singlets

B) 4 signals: all singlets

C) 3 signals: all singlets

D) 3 signals: one singlet, 2 doublets

E) 4 signals: two singlets, two doublets

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Medium

35) The ¹H NMR signal for which of the indicated protons will occur at the lowest frequency (most upfield signal)?

A) I

B) II

C) III

D) IV

E) V

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Medium

36) If all the protons of 1-fluoropentane could be discerned, which would you expect to be at the lowest field in the ¹H NMR spectrum of this compound?

A) Protons on carbon I

B) Protons on carbon II

C) Protons on carbon III

D) Protons on carbon IV

E) Protons on carbon V

Topic: Proton NMR- Chemical Shift, Splitting, Etc.

Section: 9.2

Difficulty Level: Easy

37. The ¹H NMR signal for which of the indicated protons occurs farthest downfield?

A) I

B) II

C) III

D) IV

E) V

Topic: Proton NMR- Chemical Shift, Splitting, Etc.

Section: 9.2

Difficulty Level: Hard

38) Which proton(s) of the compound below would appear as a septet in the ¹H NMR spectrum?

A) The protons on carbon I

B) The protons on carbon II

C) The protons on carbon III

D) The protons on carbon IV

E) The protons on carbon V

Topic: Proton NMR- Chemical Shift, Splitting, Etc.

Section: 9.2

Difficulty Level: Easy

39) Which proton(s) of the compound below would appear as a doublet in the ¹H NMR spectrum?

A) The protons on carbon I.

B) The protons on carbon II.

C) The protons on carbon III.

D) The protons on carbon IV.

E) The protons on carbon V.

Topic: Proton NMR- Chemical Shift, Splitting, Etc.

Section: 9.2

Difficulty Level: Easy

40) Which proton(s) of the compound below would appear as a triplet in the ¹H NMR spectrum?

A) The protons on carbon II.

B) The protons on carbon I and V.

C) The protons on carbon III and V.

D) The protons on carbon III and IV.

E) The protons on carbon V.

Topic: Proton NMR- Chemical Shift, Splitting, Etc.

Section: 9.2

Difficulty Level: Easy

41) Predict the splitting pattern you would observe for the proton at C3 of 2,3-dimethyl-2-phenylbutane.

A) Doublet

B) Singlet

C) Quartet

D) Septet

E) Octet

Topic: Proton NMR- Chemical Shift, Splitting, Etc.

Section: 9.2

Difficulty Level: Medium

42) Which of these compounds will not be represented by a singlet only in the ¹H NMR spectrum?

A) Neopentane

B) Hexamethylbenzene

C) Isobutane

D) (Z)-1,2-Dichloroethene

E) (E)-1,2-Dichloroethene

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Medium

43) Consider the expected splitting of the C2 proton signal in the ¹H NMR spectrum of 1,1-dibromopentane. Presuming that the coupling constants for neighboring protons are sufficiently different, and that the instrument has sufficient resolving power, what is the theoretical multiplicity of the C2 proton signal?

A) 3

B) 4

C) 5

D) 6

E) 8

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Hard

44) Consider the expected splitting of the C2 proton signal in the ¹H NMR spectrum of 2-ethyl-1,3-propanediol. Presuming that the coupling constants for neighboring protons are sufficiently different, and that the instrument has sufficient resolving power, what is the theoretical multiplicity of the C2 proton signal?

A) 6

B) 7

C) 8

D) 12

E) 15

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Hard

45) What is the theoretical multiplicity of the C-2 proton signal in the ¹H NMR spectrum of 2-hydroxymethyl-1,3-propanediol, shown below?

A) 1

B) 6

C) 7

D) 8

E) 9

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Hard

46) Consider the ¹H NMR spectrum of very pure 1-propanol. Assuming the maximum multiplicity of signals and non-superposition of peaks, what is the expected signal splitting pattern for each signal, in the order (a, b, c, d) ?

A) 3, 6, 4, 1

B) 3, 6, 4, 3

C) 3, 12, 3, 1

D) 3, 12, 3, 3

E) 3, 12, 6, 3

Topic: Proton NMR- Chemical Shift, Splitting, Etc.

Section: 9.2

Difficulty Level: Hard

47) The ¹H NMR spectrum of which of the compounds below, all of formula C₇H₁₂O₂, would consist of two singlets only?

A) I

B) II

C) III

D) IV

E) V

Topic: Proton NMR- Chemical Shift, Splitting, Etc.

Section: 9.2, 9.5

Difficulty Level: Medium

48) The ¹H NMR spectrum of which of the compounds below, all of formula C₇H₁₂O₂, would consist of three singlets only?

A) I

B) II

C) III

D) IV

E) V

Topic: Proton NMR- Chemical Shift, Splitting, Etc.

Section: 9.2, 9.5

Difficulty Level: Hard

49) The ¹H NMR spectrum of which of the compounds below, all of formula C₇H₁₂O₂, would consist of a singlet, a doublet and a triplet only?

A) I

B) II

C) III

D) IV

E) V

Topic: Proton NMR- Chemical Shift, Splitting, Etc.

Section: 9.2, 9.5

Difficulty Level: Hard

50) A compound with the molecular formula C₄H₁₀O gives a ¹H NMR spectrum consisting only of a quartet centered at 3.5 and a triplet at  1.1. The most likely structure for the compound is:

A)

B)

C) CH₃CH₂CH₂CH₂OH

D) CH₃CH₂OCH₂CH₃

E)

Topic: Proton NMR- Unknown Identification

Section: 9.2, 9.3, 9.5

Difficulty Level: Medium

51) What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₉H₁₀O₂? Relative integration is shown.

A)

B)

C)

D)

E)

Topic: Proton NMR- Unknown Identification

Section: 9.2, 9.3

Difficulty Level: Easy

52) What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₈H₁₄? Relative integration is shown.

A)

B)

C)

D)

E)

Topic: Proton NMR- Unknown Identification

Section: 9.2, 9.3

Difficulty Level: Easy

53) What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₆H₁₁N? In the IR spectrum you notice a stretch at about 2250 cm^-1. Relative integration is shown.

A)

B)

C)

D)

E)

Topic: Proton NMR- Unknown Identification

Section: 9.2, 9.3

Difficulty Level: Easy

54) Determine the most likely structure of a compound, with the molecular formula C₉H₁₂, which gave a ¹H NMR spectrum consisting of:

a doublet at  1.25

a septet at  2.90 and

a multiplet at  7.25

]

A) I

B) II

C) III

D) IV

E) V

Topic: Proton NMR- Unknown Identification

Section: 9.2, 9.3

Difficulty Level: Medium

55) A compound with the molecular formula C₁₀H₁₃Cl gave the following ¹H NMR spectrum:

singlet,  1.6

singlet,  3.1

multiplet,  7.2 (5H)

The most likely structure for the compound is:

A) I

B) II

C) III

D) IV

E) V

Topic: Proton NMR- Unknown Identification

Section: 9.2, 9.3

Difficulty Level: Medium

56) A compound with the molecular formula C₈H₉BrO gave the following ¹H NMR spectrum:

triplet,  1.4

quartet,  3.9

multiplet,  7.0 (4H)

There was no evidence of an -OH band in the IR spectrum. A possible structure for the compound is:

A) I

B) II

C) III

D) IV

E) V

Topic: Proton NMR- Unknown Identification

Section: 9.2, 9.3

Difficulty Level: Medium

57) A compound with the molecular formula C₆H₁₅N gave the following ¹H NMR spectrum:

triplet,  0.90

quartet,  2.4

There were no other signals. The most likely structure for the compound is:

A)

B)

C) CH₃CH₂CH₂CH₂CH₂CH₂NH₂

D)

E)

Topic: Proton NMR- Unknown Identification

Section: 9.2, 9.3

Difficulty Level: Medium

58) A compound with the molecular formula C₈H₉ClO gave the following ¹H NMR spectrum:

triplet, 3.7

triplet,  4.2

multiplet,  7.1

There was no evidence of an -OH band in the IR spectrum. The most likely structure for the compound is:

A) I

B) II

C) III

D) IV

E) V

Topic: Proton NMR- Unknown Identification

Section: 9.2, 9.3

Difficulty Level: Medium

59) A compound with the molecular formula C₃H₆Cl₂ gave a ¹H NMR spectrum consisting only of a triplet centered at 3.7 and a quintet centered at  2.2. The most likely structure for the compound is:

A) CH₃CH₂CHCl₂

B) CH₃CHClCH₂Cl

C) ClCH₂CHClCH₃

D) ClCH₂CH₂CH₂Cl

E) CH₃CCl₂CH₃

Topic: Proton NMR- Unknown Identification

Section: 9.2, 9.3

Difficulty Level: Medium

60) What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₁₀H₂₀? Relative integration is shown.

A)

B)

C)

D)

E)

Topic: Proton NMR- Unknown Identification

Section: 9.2, 9.3

Difficulty Level: Medium

61) What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₄H₈O? Relative integration is shown.

A)

B)

C)

D)

E)

Topic: Proton NMR- Unknown Identification

Section: 9.2, 9.3

Difficulty Level: Medium

62) What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₁₀H₁₂O₂? Relative integration is shown.

A)

B)

C)

D)

E)

Topic: Proton NMR- Unknown Identification

Section: 9.2, 9.3

Difficulty Level: Medium

63) What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₈H₁₆O? Relative integration is shown.

A)

B)

C)

D)

E)

Topic: Proton NMR- Unknown Identification

Section: 9.2, 9.3

Difficulty Level: Medium

64) What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₆H₁₀O₂? Relative integration is shown.

A)

B)

C)

D)

E)

Topic: Proton NMR- Unknown Identification

Section: 9.2, 9.3

Difficulty Level: Medium

65) What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₉H₁₂O? Relative integration is shown.

A)

B)

C)

D)

E)

Topic: Proton NMR- Unknown Identification

Section: 9.2, 9.3

Difficulty Level: Medium

66) What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₅H₈O? The IR spectrum does show a characteristic stretch around 1700 cm^-1. Relative integration is shown.

A)

B)

C)

D)

E)

Topic: Proton NMR- Unknown Identification

Section: 9.2, 9.3

Difficulty Level: Medium

67) A compound C₅H₁₀O gave the following spectral data:

¹H NMR spectrum IR spectrum

doublet,  1.10 strong peak

singlet,  2.10 near 1720 cm^-1

septet,  2.50

Which is a reasonable structure for the compound?

A) I

B) II

C) III

D) IV

E) V

Topic: Proton NMR- Unknown Identification

Section: 9.2, 9.3

Difficulty Level: Medium

68) A compound C₄H₉Br gave the following ¹H NMR spectrum:

triplet,  1.0 (3H); doublet,  1.7; multiplet,  1.8; multiplet, 4.1 (1H)

Which is a reasonable structure for the compound?

A) CH₃CH₂CHBrCH₃

B) CH₃CH₂CH₂CH₂Br

C) (CH₃)₂CHCH₂Br

D) (CH₃)₃CBr

Topic: Proton NMR- Unknown Identification

Section: 9.2, 9.3

Difficulty Level: Medium

69) What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₆H₁₂O which shows no characteristic stretches in the IR between 3600-3300 cm^-1, but does around 1600 cm^-1? Relative integration is shown.

A)

B)

C)

D)

E)

Topic: Proton NMR- Unknown Identification

Section: 9.2, 9.3

Difficulty Level: Hard

70) What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₆H₁₂O₂? Relative integration is shown.

A)

B)

C)

D)

E)

Topic: Proton NMR- Unknown Identification

Section: 9.2, 9.3

Difficulty Level: Hard

71) What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₆H₁₂? Relative integration is shown.

A)

B)

C)

D)

E)

Topic: Proton NMR- Unknown Identification

Section: 9.2, 9.3

Difficulty Level: Hard

72) What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₄H₇Br? Relative integration is shown.

A)

B)

C)

D)

E)

Topic: Proton NMR- Unknown Identification

Section: 9.2, 9.3

Difficulty Level: Hard

73) What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₅H₁₀O? The IR spectrum does not show any characteristic stretches around 1700 cm^-1. Relative integration is shown.

A)

B)

C)

D)

E)

Topic: Proton NMR- Unknown Identification

Section: 9.2, 9.3

Difficulty Level: Hard

74) A compound with the molecular formula C₁₀H₁₄ gave the following ¹H NMR spectrum:

doublet, 1.2

singlet,  2.3

septet,  2.8

multiplet,  7.1

A possible structure for the compound is:

A) I

B) II

C) III

D) IV

E) V

Topic: Proton NMR- Unknown Identification

Section: 9.2, 9.3

Difficulty Level: Hard

75) Determine the likely structure for a compound A (C₆H₁₀O), which is found to decolorize bromine in carbon tetrachloride. Its spectral data is as follows:

¹H NMR IR

triplet, 1.0 singlet, 2.4 2200 cm^-1 (sharp)

singlet,  1.4 singlet, 3.4 3300 cm^-1 (sharp)

quartet,  1.6 3500 cm^-1 (broad)

A) I

B) II

C) III

D) IV

E) V

Topic: Proton NMR- Unknown Identification

Section: 9.2, 9.3

Difficulty Level: Hard

76) In NMR terminology, protons H_a and H_b are said to be:

A) Identical

B) Enantiotopic

C) Diastereotopic

D) Homotopic

E) Mesotopic

Topic: Proton NMR- Chemical Shift, Splitting, Etc.

Section: 9.5

Difficulty Level: Easy

77) In the structure shown, H_a and H_b are classified as:

A) homotopic protons.

B) vicinal protons.

C) enantiotopic protons.

D) diastereotopic protons.

E) isomeric protons.

Topic: Proton NMR- Chemical Shift, Splitting, Etc.

Section: 9.5

Difficulty Level: Easy

78) In the structure shown, H_a and H_b are classified as:

A) homotopic protons.

B) vicinal protons.

C) enantiotopic protons.

D) diastereotopic protons.

E) isomeric protons.

Topic: Proton NMR- Chemical Shift, Splitting, Etc.

Section: 9.5

Difficulty Level: Medium

79) In the structure shown, H_a and H_b are classified as:

A) homotopic protons.

B) vicinal protons.

C) enantiotopic protons.

D) diastereotopic protons.

E) isomeric protons.

Topic: Proton NMR- Chemical Shift, Splitting, Etc.

Section: 9.5

Difficulty Level: Medium

80) In the structure shown, H_b and H_c are classified as:

A) homotopic protons.

B) geminal protons.

C) enantiotopic protons.

D) diastereotopic protons.

E) isomeric protons.

Topic: Proton NMR- Chemical Shift, Splitting, Etc.

Section: 9.5

Difficulty Level: Medium

81) Consider the expected splitting of signal “b” in the ¹H NMR spectrum of 1-methoxy-2-methylpropane, shown below. Presuming that J_ab is sufficiently different from J_bc and that the instrument has sufficient resolving power, what is the theoretical multiplicity of signal “b”?

A) 8

B) 9

C) 12

D) 21

E) 24

Topic: Proton NMR- Symmetry, Splitting, Chemical shift

Section: 9.2, 9.6

Difficulty Level: Easy

82) For the C2 methylene group in 1-bromopropane, the theoretical multiplicity in the ¹H NMR spectrum, presuming that J_ab is sufficiently different from J_bc and that the instrument has sufficient resolving power, is which of these?

A) 2

B) 5

C) 6

D) 8

E) 12

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2, 9.6

Difficulty Level: Hard

83) Consider the expected splitting of signal “b” in the ¹H NMR spectrum of N-methyl-1-propanamine, shown below. Presuming that J_ab is sufficiently different from J_bc and that the instrument has sufficient resolving power, what is the theoretical multiplicity of signal “b”?

A) 2

B) 5

C) 6

D) 8

E) 12

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2, 9.6

Difficulty Level: Hard

84) Consider the expected splitting of signal “b” in the ¹H NMR spectrum of 1,1-dichloro-3-methylbutane, shown below. Presuming that J_ab is sufficiently different from J_bc and that the instrument has sufficient resolving power, what is the theoretical multiplicity of signal “b”?

A) 8

B) 9

C) 12

D) 18

E) 21

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2, 9.6

Difficulty Level: Hard

85) Consider the expected splitting of signal “b” in the ¹H NMR spectrum of 1,2-dimethoxypropane, shown below. Presuming that J_bc is sufficiently different from J_bd and that the instrument has sufficient resolving power, what is the theoretical multiplicity of signal “b”?

A) 2

B) 5

C) 6

D) 8

E) 12

Topic: Proton NMR- Symmetry, Splitting, Chemical shift

Section: 9.2, 9.6

Difficulty Level: Hard

86) Consider the expected splitting of signal “c” in the ¹H NMR spectrum of 2-ethyl-1-butanol, shown below. Presuming that J_bc is sufficiently different from J_cd and that the instrument has sufficient resolving power, what is the theoretical multiplicity of signal “c”?

A) 6

B) 7

C) 8

D) 12

E) 15

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2, 9.6

Difficulty Level: Hard

87) What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₆H₁₄O₂? IR data shows no characteristic peak around 1700 cm^-1. The ¹³C-NMR chemical shifts (ppm): 108.4, 50.9, 31.6, 23.5, 2.0. Relative integration is known.

A)

B)

C)

D)

E)

Topic: Unknown Identification

Section: 9.2, 9.3, 9.8

Difficulty Level: Easy

88) What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₅H₁₁NO, which shows a characteristic stretch in the IR around 1700 cm^-1, and a characteristic peak at 202 ppm in the ¹³C-NMR? Relative integration is shown.

A)

B)

C)

D)

E)

Topic: Unknown Identification

Section: 9.2, 9.3, 9.8

Difficulty Level: Hard

89) What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₈H₁₅ClO₃, which shows a characteristic stretch in the IR around 1750 cm^-1 but not around 3500 cm^-1, and a characteristic peak at 173 ppm in the ¹³C-NMR? Relative integration is shown.

A)

B)

C)

D)

E)

Topic: Unknown Identification

Section: 9.2, 9.3, 9.8

Difficulty Level: Hard

90) What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₅H₁₁NO? In the ¹³C-NMR spectrum you notice that the farthest peak downfield has a chemical shift of 173 ppm. Relative integration is shown.

A)

B)

C)

D)

E)

Topic: Unknown Identification

Section: 9.2, 9.3, 9.8

Difficulty Level: Hard

91) The broadband proton-decoupled ¹³C NMR spectrum of a hexyl chloride exhibits five signals. Which of these structures could be the correct one for the compound?

A)

B)

C)

D)

E)

Topic: C-13 NMR- Symmetry, Chemical Shift

Section: 9.8

Difficulty Level: Easy

92) How many ¹³C signals would 1,4-dimethylbenzene give?

A) 1

B) 2

C) 3

D) 4

E) 5

Topic: C-13 NMR- Symmetry, Chemical Shift

Section: 9.8

Difficulty Level: Easy

93) How many ¹³C signals would 1,3-dichlorobenzene give?

A) 1

B) 2

C) 3

D) 4

E) 5

Topic: C-13 NMR- Symmetry, Chemical Shift

Section: 9.8

Difficulty Level: Easy

94) How many ¹³C signals would 1,2-dimethylbenzene give?

A) 1

B) 2

C) 3

D) 4

E) 5

Topic: C-13 NMR- Symmetry, Chemical Shift

Section: 9.8

Difficulty Level: Easy

95) For the compound dimedone, how many different signals would you see in the ¹³C NMR? (Assume that you can see them all.)

A) 3

B) 4

C) 5

D) 6

E) None of these choices.

Topic: C-13 NMR- Symmetry, Chemical Shift

Section: 9.8

Difficulty Level: Easy

96) For the compound adamantine, how many different signals would you see in the ¹³C NMR? (Assume that you can see them all.)

A) 1

B) 2

C) 3

D) 4

E) None of these choices.

Topic: C-13 NMR- Symmetry, Chemical Shift

Section: 9.8

Difficulty Level: Medium

97) How many ¹³C signals would you expect from anisole?

A) 1

B) 2

C) 3

D) 4

E) 5

Topic: C-13 NMR- Symmetry, Chemical Shift

Section: 9.8

Difficulty Level: Easy

98) For the following compound how many different signals would you see in the carbon NMR? (Assume that you can see them all.)

A) 3

B) 4

C) 5

D) 6

E) 7

Topic: Carbon NMR- Symmetry, Chemical Shift

Section: 9.8

Difficulty Level: Easy

99) In ¹³C NMR spectroscopy, the signal due to this type of carbon occurs furthest downfield.

A) –CN

B)

C)

D)

E) –CC–

Topic: Carbon NMR- Symmetry, Chemical Shift

Section: 9.8

Difficulty Level: Easy

100) The C₇ compound which gives 3 signals in the broadband proton-decoupled ¹³C spectrum could be:

A) Heptane

B) 2-Methylhexane

C) 3,3-Dimethylpentane

D) 2,4-Dimethylpentane

E) 2,2,3-Trimethylbutane

Topic: C-13 NMR- Symmetry, Chemical Shift

Section: 9.8

Difficulty Level: Medium

101) For the following compound how many different signals would you see in the carbon NMR? (Assume that you can see them all.)

A) 1

B) 2

C) 3

D) 4

E) 5

Topic: Carbon NMR- Symmetry, Chemical Shift

Section: 9.8

Difficulty Level: Medium

102) For the following compound how many different signals would you see in the carbon NMR? (Assume that you can see them all.)

A) 4

B) 5

C) 6

D) 7

E) 8

Topic: Carbon NMR- Symmetry, Chemical Shift

Section: 9.8

Difficulty Level: Medium

103) For the following compound how many different signals would you see in the carbon NMR? (Assume that you can see them all.)

A) 3

B) 4

C) 5

D) 8

E) 9

Topic: Carbon NMR- Symmetry, Chemical Shift

Section: 9.8

Difficulty Level: Medium

104) A bromodichlorobenzene which gives four signals in the broadband proton-decoupled ¹³C spectrum could be:

A) I

B) II

C) III

D) IV

E) V

Topic: Carbon NMR- Symmetry, Chemical Shift

Section: 9.8

Difficulty Level: Medium

105) For the following compound how many different signals would you see in the carbon NMR? (Assume that you can see them all.)

A) 4

B) 5

C) 6

D) 7

E) 8

Topic: Carbon NMR- Symmetry, Chemical Shift

Section: 9.8

Difficulty Level: Hard

106) Which compound below would give rise to 3 signals in the proton NMR spectrum and 4 signals in the carbon NMR spectrum? (Assume you can separate and see all peaks.)

A) I

B) II

C) III

D) IV

E) None of these choices.

Topic: Carbon NMR and Proton NMR- Symmetry, Chemical Shift

Section: 9.2, 9.8

Difficulty Level: Medium

107) Which compound below would give rise to 4 signals in the proton NMR spectrum and 4 signals in the carbon NMR spectrum? (Assume you can separate and see all peaks.)

A) I

B) II

C) III

D) IV

E) More than one of the above.

Topic: Carbon NMR and Proton NMR- Symmetry, Chemical Shift

Section: 9.2, 9.8

Difficulty Level: Hard

108) Which compound below would give rise to 4 signals in the proton NMR spectrum and 6 signals in the carbon NMR spectrum? (Assume you can separate and see all peaks.)

A) I

B) II

C) III

D) IV

E) More than one of these choices.

Topic: Carbon NMR and Proton NMR- Symmetry, Chemical Shift

Section: 9.2, 9.8

Difficulty Level: Hard

109) Which compound below would not give rise to 4 signals in the proton NMR spectrum and 3 signals in the carbon NMR spectrum? (Assume you can separate and see all peaks.)

A) I

B) II

C) III

D) IV

E) All of these choices fit the criteria.

Topic: Carbon NMR and Proton NMR- Symmetry, Chemical Shift

Section: 9.2, 9.8

Difficulty Level: Hard

110) Which compound below would give rise to 5 signals in the proton NMR spectrum and 7 signals in the carbon NMR spectrum? (Assume you can separate and see all peaks.)

A) I

B) II

C) III

D) IV

E) None of these choices.

Topic: Carbon NMR and Proton NMR- Symmetry, Chemical Shift

Section: 9.2, 9.8

Difficulty Level: Hard

111) What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₇H₁₂O₄? The ¹³C-NMR spectrum shows peaks at 14.1, 40.8, 61.0 and 166.8 ppm. Relative integration is shown.

A)

B)

C)

D)

E)

Topic: Unknown Identification

Section: 9.2, 9.3, 9.8

Difficulty Level: Medium

112) What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₁₀H₁₁N? Looking at the ¹³C-NMR you notice 10 distinct peaks, and the IR has a characteristic peak around 2250 cm^-1. Relative integration is shown.

A)

B)

C)

D)

E)

Topic: Unknown Identification

Section: 9.2, 9.3, 9.8

Difficulty Level: Medium

113) What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₆H₁₀O₂? The ¹³C-NMR shows characteristic chemical shifts at 22.3, 31.1, 117.3, 157.7, and 171.6 ppm. Relative integration is shown.

A)

B)

C)

D)

E)

Topic: Unknown Identification

Section: 9.2, 9.3, 9.8

Difficulty Level: Medium

114) What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₁₁H₁₄O₂? Looking at the ¹³C-NMR you notice a peak at 174 ppm. Relative integration is shown.

A)

B)

C)

D)

E)

Topic: Unknown Identification

Section: 9.2, 9.3, 9.8

Difficulty Level: Medium

115) What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₁₂H₁₇NO and a characteristic IR stretch near 1700 cm^-1 and a characteristic peak in the ¹³C-NMR at 170 ppm? Relative integration is shown.

A)

B)

C)

D)

E)

Topic: Unknown Identification.

Section: 9.2, 9.3, 9.8

Difficulty Level: Medium

116) What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₉H₁₈O₂ and characteristic ¹³C-NMR peaks at 11.3, 21.6, 25.3, 49.4, 67.1, and 175.5 ppm? Relative integration is shown.

A)

B)

C)

D)

E)

Topic: Unknown Identification

Section: 9.2, 9.3, 9.8

Difficulty Level: Medium

117) Which is the base peak?

A) 15

B) 29

C) 44

D) 45

E) 100

Topic: Mass Spectrometry

Section: 9.10

Difficulty Level: Easy

118) Which is the likely molecular ion (M)?

A) 15

B) 29

C) 44

D) 45

E) 100

Topic: Mass Spectrometry

Section: 9.10

Difficulty Level: Easy

119) A prominent (M^_-18) peak suggests that the compound might be a(n):

A) Alkane

B) Alcohol

C) Ether

D) Ketone

E) Primary amine

Topic: Mass Spectrometry

Section: 9.13

Difficulty Level: Easy

120) Predict the base peak for 2-chloro-2-methylpropane,

A) m/z 15

B) m/z 92

C) m/z 43

D) m/z 57

E) m/z 77

Topic: Mass Spectrometry

Section: 9.13

Difficulty Level: Medium

121) An organic compound absorbs strongly in the IR at 1687 cm^-1. Its ¹H NMR spectrum consists of two signals, a singlet at 2.1 ppm and a multiplet centered at 7.1 ppm. Its mass spectrum shows significant peaks at m/z 120, m/z 105 and m/z 77. This information is consistent with which of the following structures?

A) I

B) II

C) III

D) IV

E) V

Topic: Structure Elucidation

Section: 2.16, 9.2, 9.13

Difficulty Level: Medium

122) Select the structure of a compound C₆H₁₄ with a base peak at m/z 43.

A) CH₃CH₂CH₂CH₂CH₂CH₃

B) (CH₃CH₂)₂CHCH₃

C) (CH₃)₃CCH₂CH₃

D) (CH₃)₂CHCH(CH₃)₂

E) None of these choices.

Topic: Mass Spectrometry

Section: 9.13

Difficulty Level: Medium

123) What is the molecular formula of this compound?

m/z intensity

84 M^_ 10.00

85 0.56

86 0.04

A) C₅H₁₀O

B) C₅H₈O

C) C₅H₂₄

D) C₆H₁₂

E) C₄H₆O₂

Topic: Mass Spectrometry

Section: 9.14

Difficulty Level: Medium

124) What is the molecular formula of this compound?

m/z intensity

78 M^_ 10.00

79 1

80 3.3

81 0.3

A) C₆H₆

B) C₃H₅Cl

C) C₆H₈

D) C₆H₉

E) C₃H₇Cl

Topic: Mass Spectrometry

Section: 9.14

Difficulty Level: Medium

125) The mass spectra of alkyl bromides and chlorides are characterized by an unusually intense ___.

A) base peak

B) parent peak

C) M^_{}peak

D) M^_ +2 peak

E) None of these choices.

Topic: Mass Spectrometry

Section: 9.14

Difficulty Level: Easy

126) The data below from the molecular ion region of the mass spectrum of a halogen-containing compound are consistent with the presence of what halogen(s) in the original compound?

intensity

M^_51.0

M^_+2 100.0

M^_+4 49.0

A) One Br

B) One Cl

C) One Br and one Cl

D) Two Br

E) Two Cl

Topic: Mass Spectrometry

Section: 9.14

Difficulty Level: Hard

Question type: True/False

127) All of the hydrogen atoms in a molecule of cyclohexane are homotopic.

Topic: Proton Equivalence

Section: 9.5

Difficulty Level: Easy

128) Hydrogen that are diastereotopic will show different chemical signals in the proton NMR.

Topic: Proton Equivalence

Section: 9.5

Difficulty Level: Medium

129) The predicted ratio of the relative peak sizes in a quintet signal would be about 1:3:5:3:1.

Topic: Proton NMR Splitting Patterns

Section: 9.6

Difficulty Level: Easy

130) An acceptable solvent to use for a deuterium exchange experiment with an alcohol would be CDCl₃.

Topic: Chemical Exchange

Section: 9.7

Difficulty Level: Medium

131) Compounds that contain a benzylic carbon will often show a peak with a m/z of 91 in a mass spectrometry experiment.

Topic: Mass Spectroscopy

Section: 9.13

Difficulty Level: Hard

Question type: fill-in-the-blank

132“NMR” stands for ___.

Topic: General

Section: 9.1

Difficulty Level: Easy

Question type: Essay

133) Briefly explain how you might distinguish between 1-butyne and 2-butyne by comparing their ¹H-NMR spectra.

Topic: Structure Elucidation

Section: 9.2

Difficulty Level: Easy

134) Briefly explain how you might distinguish between the following substances by comparing their ¹H-NMR spectra:

Topic: Structure Elucidation

Section: 9.2

Difficulty Level: Medium

135) Briefly explain how you might distinguish between the following substances by comparing their ¹H-NMR spectra:

Topic: Structure Elucidation

Section: 9.2

Difficulty Level: Medium

136) Briefly explain how you might distinguish between the following substances by comparing their ¹H-NMR spectra:

The methine proton in I is likely to be more deshielded, and produce a signal (septet) at about 3.5 ppm, while the analogous proton in II is likely to be found, also as a septet, at about 2.3 ppm.

By contrast, the methylene proton in II is likely to be more deshielded, and produce a signal (triplet) at about 3.4 ppm, while the analogous proton in II is likely to be found, also as a triplet, at about 2.2 ppm.

Topic: Structure Elucidation

Section: 9.2

Difficulty Level: Medium

137) Briefly explain how you might distinguish between the following substances by comparing their ¹H-NMR spectra:

The methine proton in I is likely to be more deshielded, and produce a signal (septet) at about 3.5 ppm, while the analogous proton in II is likely to be found, also as a septet, at about 2.3 ppm.

By contrast, the methylene proton in II is likely to be more deshielded, and produce a signal (triplet) at about 3.4 ppm, while the analogous proton in II is likely to be found, also as a triplet, at about 2.2 ppm.

Topic: Structure Elucidation

Section: 9.2

Difficulty Level: Medium

138) Draw the structure for a compound that has the chemical formula C₄H₈O and shows one singlet, one triplet and one quartet in the proton NMR.

Topic: Structure Elucidation

Section: 9.2

Difficulty Level: Medium

139) Predict the ¹H NMR spectrum of diethoxymethane, CH₃CH₂OCH₂OCH₂CH₃.

Topic: ¹H NMR

Section: 9.2

Difficulty Level: Medium

140) Predict the ¹H NMR spectrum of 2-chloroethanal, CH₂ClCHO.

Topic: ¹H NMR

Section 9.2

Difficulty Level: Medium

141) Predict the number of signals in the ¹H NMR spectrum of 2-methyl-2-pentanol.

Topic: ¹H NMR

Section: 9.2

Difficulty Level: Easy

142) When measuring the integral for a particular peak in the NMR spectrum, we are not interested in the peak height as much as in the ___.

Topic: General, Signal Integration

Section: 9.2

Difficulty Level: Easy

143) Examine the ¹H NMR spectrum of 1-nitropropane, shown below. Assign the signals to the respective hydrogen atoms in the molecule.

Topic: Structure Elucidation

Section: 9.2, 9.3

Difficulty Level: Easy

144) An unknown compound, A, has the formula C₇H₁₄O. Elucidate the structure of A by scrutinizing its IR and¹H NMR spectra, shown below.

4-Heptanone

Topic: Structure Elucidation

Section: 2.16, 9.2, 9.3

Difficulty Level: Medium

145) Which form of electromagnetic radiation possesses the least energy?

Topic: General

Section: 9.4

Difficulty Level: Easy

146) What compound is used as the standard “zero” reference in both carbon and proton NMR?

Topic: Reference Compound

Section: 9.4, 9.5

Difficulty Level: Easy

147) Name two rapid processes that occur in organic molecules.

Topic: General, Bond Rotation, Proton Exchange

Section: 9.7

Difficulty Level: Medium

148) Predict the ¹H NMR spectrum of cis-1,4-cyclohexanediol if we perform the experiment in CD₃OD.

Topic: Rapid Chemical Exchange

Section: 9.7

Difficulty Level: Hard

149) Interpret the following ¹³C/DEPT spectrum of a compound C₅H₁₀Br₂: elucidate the structure and assign all the ¹³C resonances.

Topic: ¹³C NMR, Structure Elucidation

Section: 9.8

Difficulty Level: Medium

150) An unknown compound, C, has the formula C₇H₇Br. Elucidate the structure of C by scrutinizing its IR, ¹H NMR and ¹³C NMR spectra, shown below.

4-Bromotoluene

Topic: Structure Elucidation

Section: 2.16, 9.2, 9.3, 9.8

Difficulty Level: Medium

151) An unknown compound, F, has the formula C₃H₆O₂. Elucidate the structure of F by scrutinizing its IR, ¹H NMR and ¹³C NMR spectra, shown below.

Propanoic acid

Topic: Structure Elucidation

Section: 2.16, 9.2, 9.3. 9.8

Difficulty Level: Medium

152) An unknown compound, L, has the formula C₅H₁₀O₂. Elucidate the structure of L by scrutinizing its IR, ¹H NMR and ¹³C NMR spectra, shown below.

Methyl butyrate

Topic: Structure Elucidation

Section: 2.16, 9.2, 9.3, 9.8

Difficulty Level: Medium

153) An unknown compound, I, has the formula C₃H₇NO₂. Elucidate the structure of I by scrutinizing its IR, ¹H NMR and ¹³C NMR spectra, shown below.

1-Nitropropane

Topic: Structure Elucidation

Section: 2.16, 9.2, 9.3, 9.8

Difficulty Level: Hard

154) An unknown compound, E, has the formula C₆H₁₂O. Elucidate the structure of E by scrutinizing its IR, ¹H NMR and ¹³C NMR spectra, shown below.

2-Hexanone

Topic: Structure Elucidation

Section: 2.16, 9.2, 9.3, 9.8

Difficulty Level: Hard

155) An unknown compound, U, has the formula C₆H₄Cl₂O. Elucidate the structure of U by scrutinizing its IR, ¹H NMR and ¹³C NMR spectra, shown below.

2,6-dichlorophenol

Topic: Structure Elucidation

Section: 2.16, 9.2, 9.3, 9.8

Difficulty Level: Hard

156) Explain the key differences in the 2-dimensional NMR techniques known as COSY and heteronuclear correlations.

Topic: Two-Dimensional NMR

Section: 9.9

Difficulty Level: Easy

157) An unknown compound, V, has the formula C₈H₁₀O. Elucidate the structure of V by scrutinizing its IR, ¹H NMR and ¹³C NMR spectra, shown below.

2,6-dimethylphenol

Topic: Structure Elucidation

Section: 2.16, 9.2, 9.3, 9.8

Difficulty Level: Hard

Question type: fill-in-the-blank

158) In mass spectrometry, the most intense peak is assigned an intensity of 100%, and is referred to as the ___.

Topic: Base Peak

Section: 9.10

Difficulty Level: Easy

159) A mass spectrometer sorts ions on the basis of their ___.

Topic: m/z Ratio

Section: 9.10

Difficulty Level: Easy

160) In electron impact mass spectrometry, a beam of high-energy electrons initially dislodges one electron from the compound being studied. This produces a positively charged ion called the ___.

Topic: Molecular Ion

Section: 9.11

Difficulty Level: Easy

Question type: Essay

161) What can be determined from the relative abundance of the M^_ +1 peak?

Topic: Relative Abundance

Section: 9.14

Difficulty Level: Easy

162) How many signals would you expect to find in the ¹H NMR spectrum of CH₃OCH₂CH₂CH₂OCH₃?

A) 1

B) 2

C) 3

D) 4

E) 5

Topic: Proton NMR- Chemical Shift, Splitting, Etc.

Section: 9.2

Difficulty Level: Easy

163) The ¹H NMR spectrum of which of these compounds would consist of only singlets?

A) 2-chloro-4-methylpentane

B) 3-chloro-2-methylpentane

C) 3-chloropentane

D) 1-chloro-2,2-dimethylpropane

E) 3-chloro-3-methylpentane

Topic: Proton NMR- Chemical Shift, Splitting, Etc.

Section: 9.2

Difficulty Level: Medium

164) A compound that would show a doublet and a quartet in the ¹H NMR spectrum could be:

A) 3-ethylpentane

B) 2-bromopropane

C) chlorocyclopropane

D) 1-iodopropane

E) none of these choices

Topic: Proton NMR- Symmetry, Splitting, Chemical Shift

Section: 9.2

Difficulty Level: Medium

165) If all the protons of 1-fluoropentane could be discerned, which would you expect to be at the highest field in the ¹H NMR spectrum of this compound?

A) Protons on carbon I

B) Protons on carbon II

C) Protons on carbon III

D) Protons on carbon IV

E) Protons on carbon V

Topic: Proton NMR- Chemical Shift, Splitting, Etc.

Section: 9.2

Difficulty Level: Easy

166) Which compound below would give rise to 4 signals in the proton NMR spectrum and 4 signals in the carbon NMR spectrum? (Assume you can separate and see all peaks.)

A) I

B) II

C) III

D) IV

E) None of these choices.

Topic: Carbon NMR and Proton NMR- Symmetry, Chemical Shift

Section: 9.2, 9.8

Difficulty Level: Hard

167) Which compound below would give rise to 7 signals in the proton NMR spectrum and 7 signals in the carbon NMR spectrum? (Assume you can separate and see all peaks.)

A) I

B) II

C) III

D) IV

E) None of these choices.

Topic: Carbon NMR and Proton NMR- Symmetry, Chemical Shift

Section: 9.2, 9.8

Difficulty Level: Hard

168) Which compound below would give rise to 5 signals in the proton NMR spectrum and 5 signals in the carbon NMR spectrum? (Assume you can separate and see all peaks.)

A) I

B) II

C) III

D) IV

E) None of these choices.

Topic: Carbon NMR and Proton NMR- Symmetry, Chemical Shift

Section: 9.2, 9.8

Difficulty Level: Hard