In the presence of an external magnetic field the approximate ratio of 1H nuclei with α spins compared to β spins is respectively: ________.

A) 90:10 B) 25:75 C) 50:50 D) 75:25 A) 90:10 B) 25:75 C) 50:50 D) 75:25 C

How many peaks appear in the proton spin decoupled 13 C NMR spectrum of the compound below?

A) 1 B) 2 C) 3 D) 4 E) 5 A) 1 B) 2 C) 3 D) 4 E) 5

Exam 13: Nuclear Magnetic Resonance Spectroscopy

Deduce the identity of the compound whose molecular formula is C₄H₈O₃ from the spectral data provided: IR (cm^-1): 2800-3300 (broad), 2950, 1750; ¹³C NMR (δ): 17.7 (q), 65.4 (q), 72.3 (d), 210.8 (s) (ppm)

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Question 1

Correct Answer:

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CH₃OCH(CH₃)CO₂H

Deduce the identity of the following compound from the ¹H NMR data given. C₇H₁₂O₄: δ 1.3 (6H, triplet), 3.4 (2H, singlet), 4.2 (4H, quartet) (ppm)

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Question 2

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CH₂(CO₂CH₂CH₃)₂

In the presence of an external magnetic field the approximate ratio of ¹H nuclei with α spins compared to β spins is respectively: ________.

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Question 3

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The protons marked H_a and H_b in the molecule below are ________.

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Question 4

Which of the following functional groups has the most deshielded proton and would be predicted to show an NMR signal that is the farthest downfield?

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Question 5

Predict the number of signals expected (disregarding splitting) in the ¹H spectrum of dibutyl ether.

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Question 6

Deduce the identity of the following compound from the ¹H NMR data given. C₃H₆Br₂: δ 2.4 (2H, quintet), 3.5 (4H, triplet) (ppm)

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Question 7

A peak split into a doublet of triplets gave the following measurements in its splitting pattern. State the coupling constants (J values) for both the doublet and the triplet.

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Question 8

Deduce the identity of the following compound from the ¹H NMR data given. C₅H₁₂O: δ 1.0 (3H, triplet), 1.2-1.8 (6H, multiplet), 3.0 (1H, broad singlet), 3.8 (2H, triplet) (ppm)

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Question 9

Predict the number of signals expected, their splitting, and their relative area in the ¹H NMR spectrum of 1,2-dichloroethane (ClCH₂CH₂Cl).

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Question 10

Calculate the magnetic field that corresponds to the proton resonance frequency of 300.00 MHz. The gyromagnetic ratio of the ¹H nucleus is 26,753 s^-1 gauss^-1.

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Question 11

Deduce the identity of the following compound from the ¹H NMR data given. C₆H₁₀O₂: δ 2.19 (3H, singlet), 2.70 (2H, singlet) (ppm)

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Question 12

Predict the number of signals expected (disregarding splitting) in the ¹H spectrum of 1,1-dimethylcyclobutane.

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Question 13

Provide a structure that is consistent with the data below. C₇H₁₆O IR (cm^-1): 3200-3600 (broad), 2950 ¹H NMR ( d): 2.9 (1H, broad s), 1.2 (6H, q), 0.9 (9H, t) ¹³C NMR (d ): 70 (s), 25 (t), 12 (q)

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Question 14

Predict the number of signals expected in the proton spin decoupled ¹³C NMR spectrum of the compound shown below.

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Question 15

Predict the number of signals expected (disregarding splitting) in the ¹H NMR spectrum of the compound shown below.

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Question 16

Provide a structure that is consistent with the data below. C₅H₁₀O IR (cm^-1): 2950 ¹H NMR ( d): 3.5 (4H, s), 0.9 (6H, s) ¹³C NMR (d ): 64 (t), 41 (s), 12 (q)

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Question 17

What compound exhibits three singlets in its proton spin decoupled ¹³C NMR spectrum?

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Question 18

The following splitting pattern represents one of the vinyl protons of styrene. Identify which proton is represented and list all the coupling constants (J values) for the splitting pattern.

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Question 19

How many peaks appear in the proton spin decoupled ¹³C NMR spectrum of the compound below?

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Question 20

Showing 1 - 20 of 130

Exam 13: Nuclear Magnetic Resonance Spectroscopy

Deduce the identity of the compound whose molecular formula is C4H8O3 from the spectral data provided: IR (cm-1): 2800-3300 (broad), 2950, 1750; 13C NMR (δ): 17.7 (q), 65.4 (q), 72.3 (d), 210.8 (s) (ppm)

Deduce the identity of the following compound from the 1H NMR data given. C7H12O4: δ 1.3 (6H, triplet), 3.4 (2H, singlet), 4.2 (4H, quartet) (ppm)

In the presence of an external magnetic field the approximate ratio of 1H nuclei with α spins compared to β spins is respectively: ________.

The protons marked Ha and Hb in the molecule below are ________.

Which of the following functional groups has the most deshielded proton and would be predicted to show an NMR signal that is the farthest downfield?

Predict the number of signals expected (disregarding splitting) in the 1H spectrum of dibutyl ether.

Deduce the identity of the following compound from the 1H NMR data given. C3H6Br2: δ 2.4 (2H, quintet), 3.5 (4H, triplet) (ppm)

A peak split into a doublet of triplets gave the following measurements in its splitting pattern. State the coupling constants (J values) for both the doublet and the triplet.

Deduce the identity of the following compound from the 1H NMR data given. C5H12O: δ 1.0 (3H, triplet), 1.2-1.8 (6H, multiplet), 3.0 (1H, broad singlet), 3.8 (2H, triplet) (ppm)

Predict the number of signals expected, their splitting, and their relative area in the 1H NMR spectrum of 1,2-dichloroethane (ClCH2CH2Cl).

Calculate the magnetic field that corresponds to the proton resonance frequency of 300.00 MHz. The gyromagnetic ratio of the 1H nucleus is 26,753 s-1 gauss-1.

Deduce the identity of the following compound from the 1H NMR data given. C6H10O2: δ 2.19 (3H, singlet), 2.70 (2H, singlet) (ppm)

Predict the number of signals expected (disregarding splitting) in the 1H spectrum of 1,1-dimethylcyclobutane.

Provide a structure that is consistent with the data below. C7H16O IR (cm-1): 3200-3600 (broad), 2950 1H NMR ( d): 2.9 (1H, broad s), 1.2 (6H, q), 0.9 (9H, t) 13C NMR (d ): 70 (s), 25 (t), 12 (q)

Predict the number of signals expected in the proton spin decoupled 13C NMR spectrum of the compound shown below.

Predict the number of signals expected (disregarding splitting) in the 1H NMR spectrum of the compound shown below.

Provide a structure that is consistent with the data below. C5H10O IR (cm-1): 2950 1H NMR ( d): 3.5 (4H, s), 0.9 (6H, s) 13C NMR (d ): 64 (t), 41 (s), 12 (q)

What compound exhibits three singlets in its proton spin decoupled 13C NMR spectrum?

The following splitting pattern represents one of the vinyl protons of styrene. Identify which proton is represented and list all the coupling constants (J values) for the splitting pattern.

How many peaks appear in the proton spin decoupled 13 C NMR spectrum of the compound below?

Introduction and Review

Structure and Properties of Organic Molecules

Structure and Stereochemistry of Alkanes

The Study of Chemical Reactions

Stereochemistry

Alkyl Halides: Nucleophilic Substitution and Elimination

Structure and Synthesis of Alkenes

Reactions of Alkenes

Alkynes

Structure and Synthesis of Alcohols

Reactions of Alcohols

Infrared Spectroscopy and Mass Spectrometry

Ethers, Epoxides, and Thioethers

Conjugated Systems, Orbital Symmetry, and Ultraviolet Spectroscopy

Aromatic Compounds

Reactions of Aromatic Compounds

Ketones and Aldehydes

Amines

Carboxylic Acids

Carboxylic Acid Derivatives

Condensations and Alpha Substitutions of Carboxyl Compounds

Carbohydrates and Nucleic Acids

Amino Acids, Peptides, and Proteins

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Deduce the identity of the compound whose molecular formula is C₄H₈O₃ from the spectral data provided: IR (cm^-1): 2800-3300 (broad), 2950, 1750; ¹³C NMR (δ): 17.7 (q), 65.4 (q), 72.3 (d), 210.8 (s) (ppm)

Deduce the identity of the following compound from the ¹H NMR data given. C₇H₁₂O₄: δ 1.3 (6H, triplet), 3.4 (2H, singlet), 4.2 (4H, quartet) (ppm)

In the presence of an external magnetic field the approximate ratio of ¹H nuclei with α spins compared to β spins is respectively: ________.

The protons marked H_a and H_b in the molecule below are ________.

Predict the number of signals expected (disregarding splitting) in the ¹H spectrum of dibutyl ether.

Deduce the identity of the following compound from the ¹H NMR data given. C₃H₆Br₂: δ 2.4 (2H, quintet), 3.5 (4H, triplet) (ppm)

Deduce the identity of the following compound from the ¹H NMR data given. C₅H₁₂O: δ 1.0 (3H, triplet), 1.2-1.8 (6H, multiplet), 3.0 (1H, broad singlet), 3.8 (2H, triplet) (ppm)

Predict the number of signals expected, their splitting, and their relative area in the ¹H NMR spectrum of 1,2-dichloroethane (ClCH₂CH₂Cl).

Calculate the magnetic field that corresponds to the proton resonance frequency of 300.00 MHz. The gyromagnetic ratio of the ¹H nucleus is 26,753 s^-1 gauss^-1.

Deduce the identity of the following compound from the ¹H NMR data given. C₆H₁₀O₂: δ 2.19 (3H, singlet), 2.70 (2H, singlet) (ppm)

Predict the number of signals expected (disregarding splitting) in the ¹H spectrum of 1,1-dimethylcyclobutane.

Provide a structure that is consistent with the data below. C₇H₁₆O IR (cm^-1): 3200-3600 (broad), 2950 ¹H NMR ( d): 2.9 (1H, broad s), 1.2 (6H, q), 0.9 (9H, t) ¹³C NMR (d ): 70 (s), 25 (t), 12 (q)

Predict the number of signals expected in the proton spin decoupled ¹³C NMR spectrum of the compound shown below.

Predict the number of signals expected (disregarding splitting) in the ¹H NMR spectrum of the compound shown below.

Provide a structure that is consistent with the data below. C₅H₁₀O IR (cm^-1): 2950 ¹H NMR ( d): 3.5 (4H, s), 0.9 (6H, s) ¹³C NMR (d ): 64 (t), 41 (s), 12 (q)

What compound exhibits three singlets in its proton spin decoupled ¹³C NMR spectrum?

How many peaks appear in the proton spin decoupled ¹³C NMR spectrum of the compound below?