Question 1

Identify the type of coupling that exists between the two protons in the following compound, given that the compound is asymmetrical. ​

Accepted Answer

A)  Geminal coupling 
B)  Vicinal coupling 
C)  Long-range coupling 
D)  Single-bond coupling 
A)  Geminal coupling 
B)  Vicinal coupling 
C)  Long-range coupling 
D)  Single-bond coupling

Question 2

The splitting of signals in the 1H NMR spectrum provides information about the number of neighboring protons of each proton in the compound.

Accepted Answer

A) True 
 B)False

Question 3

Identify the compound (C4H8O) that gives the following 1H NMR spectrum.

Accepted Answer

Question 4

For each of the compounds below tell how many signals you would expect the molecule to have in its normal, broadband hydrogen-decoupled S1U1P113S1S1P0C NMR spectra. Enter the numerical value in the blank provided to the left of the structure.
-_______

Accepted Answer

The answer of For each of the compounds below tell...

Question 5

Which of the following combinations of peaks appears in the 1H NMR spectrum of butane?

Accepted Answer

A)  a triplet and a doublet 
B)  a triplet and a quartet 
C)  a triplet and a sextet 
D)  two singlets 
A)  a triplet and a doublet 
B)  a triplet and a quartet 
C)  a triplet and a sextet 
D)  two singlets

Question 6

Identify the compound (C8H10) that gives the following 1H NMR spectrum.

Accepted Answer

m-xylene (

Question 7

Which of the protons in the following molecule appear furthest downfield in the 1H NMR spectrum? $\mathrm{CH}_{3}-\mathrm{CH}_{2}-\mathrm{CH}_{2}-\mathrm{CH}_{2}-\mathrm{Cl}$
$\quad$i $\quad$$\quad$$\quad$ii$\quad$$\quad$ iii $\quad$$\quad$iv

Accepted Answer

A)  i 
B)  ii 
C)  iii 
D)  iv 
A)  i 
B)  ii 
C)  iii 
D)  iv

Question 8

Consider the following structure. Answer the following questions by placing the appropriate number in the blank to the left.  
-_____The number of signals in the hydrogen-decoupled 13C NMR of this compound.

Accepted Answer

Question 9

On which factor is chemical shielding not dependent?

Accepted Answer

A)  Hybridization of adjacent atoms 
B)  Electronegativity of nearby atoms 
C)  Karplus curve to plot dihedral angles 
D)  Magnetic induction within an adjacent pi bond 
A)  Hybridization of adjacent atoms 
B)  Electronegativity of nearby atoms 
C)  Karplus curve to plot dihedral angles 
D)  Magnetic induction within an adjacent pi bond

Question 10

What is the splitting of the signal in the 1H NMR spectrum for the methyl protons of ethane?

Accepted Answer

A)  singlet 
B)  doublet 
C)  triplet 
D)  quartet 
A)  singlet 
B)  doublet 
C)  triplet 
D)  quartet

Question 11

What is the hydrogen deficiency index for a compound with a molecular formula of C10H16O2?

Accepted Answer

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

Question 12

Which C8H10 compound gives the following 1H NMR spectrum?

Accepted Answer

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

Question 13

Consider the following structure. Answer the following questions by placing the appropriate number in the blank to the left.  
-_____The number of nonequivalent hydrogen atoms in this compound.

Accepted Answer

The answer of Consider the following structure. Answer the following...

Question 14

Which C9H10O compound gives the following 1H NMR spectrum?

Accepted Answer

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

Question 15

Which feature in the 1H NMR spectrum provides information about the electronic environment of the protons in a compound?

Accepted Answer

A)  number of signals 
B)  integral 
C)  splitting 
D)  chemical shift 
A)  number of signals 
B)  integral 
C)  splitting 
D)  chemical shift

Question 16

Which of the protons in the following molecule appear furthest downfield in the 1H NMR spectrum? $\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$O
$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$$\quad$||
$\mathrm{H}_{3} \mathrm{C}-\mathrm{O}-\mathrm{CH}_{2}-\mathrm{CH}_{2}-\mathrm{C}-\mathrm{H}$
$\quad$i$\quad$$\quad$$\quad$$\quad$$\quad$ ii$\quad$$\quad$ iii$\quad$$\quad$$\quad$ iv

Accepted Answer

A)  i 
B)  ii 
C)  iii 
D)  iv 
A)  i 
B)  ii 
C)  iii 
D)  iv

Question 17

Nuclear magnetic resonance spectroscopy provides information about a molecule's carbon-hydrogen framework.

Accepted Answer

A) True 
 B)False

Question 18

Consider the following structure.   If the proton attached to C2 in 1,1,2-tribromopropane is coupled with the protons on C1 (J = 3.6 Hz) and C3 (J = 6.8), the tree diagram of the C2 proton is shown below.

Accepted Answer

A) True 
 B)False

Question 19

Which C4H9Br compound gives a doublet at approximately 3.3 ppm in the 1H NMR spectrum?

Accepted Answer

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

Question 20

Which of the following is not true regarding 1H NMR spectroscopy?

Accepted Answer

A)  a "downfield" peak appears at a lower value of δ 
B)  on a 300 MHz instrument, a proton that adsorbs irradiation at a frequency 900 Hz higher than the adsorption of TMS appears at δ 3 ppm. 
C)  δ for a particular proton is independent of the magnetic field strength of the instrument used. 
D)  "deshielding" leads to peaks at higher values of δ 
A)  a "downfield" peak appears at a lower value of δ 
B)  on a 300 MHz instrument, a proton that adsorbs irradiation at a frequency 900 Hz higher than the adsorption of TMS appears at δ 3 ppm. 
C)  δ for a particular proton is independent of the magnetic field strength of the instrument used. 
D)  "deshielding" leads to peaks at higher values of δ

Exam 13: Nuclear Magnetic Resonance Spectroscopy

Identify the type of coupling that exists between the two protons in the following compound, given that the compound is asymmetrical. ​

The splitting of signals in the 1H NMR spectrum provides information about the number of neighboring protons of each proton in the compound.

Identify the compound (C4H8O) that gives the following 1H NMR spectrum.

For each of the compounds below tell how many signals you would expect the molecule to have in its normal, broadband hydrogen-decoupled 13C NMR spectra. Enter the numerical value in the blank provided to the left of the structure. -_______

Which of the following combinations of peaks appears in the 1H NMR spectrum of butane?

Identify the compound (C8H10) that gives the following 1H NMR spectrum.

Which of the protons in the following molecule appear furthest downfield in the 1H NMR spectrum? CH3−CH2−CH2−CH2−Cl\mathrm{CH}_{3}-\mathrm{CH}_{2}-\mathrm{CH}_{2}-\mathrm{CH}_{2}-\mathrm{Cl}CH3​−CH2​−CH2​−CH2​−Cl \quad i \quad\quad\quad ii \quad\quad iii \quad\quad iv

Consider the following structure. Answer the following questions by placing the appropriate number in the blank to the left. -_____The number of signals in the hydrogen-decoupled 13C NMR of this compound.

On which factor is chemical shielding not dependent?

What is the splitting of the signal in the 1H NMR spectrum for the methyl protons of ethane?

What is the hydrogen deficiency index for a compound with a molecular formula of C10H16O2?

Which C8H10 compound gives the following 1H NMR spectrum?

Consider the following structure. Answer the following questions by placing the appropriate number in the blank to the left. -_____The number of nonequivalent hydrogen atoms in this compound.

Which C9H10O compound gives the following 1H NMR spectrum?

Which feature in the 1H NMR spectrum provides information about the electronic environment of the protons in a compound?

Nuclear magnetic resonance spectroscopy provides information about a molecule's carbon-hydrogen framework.

Consider the following structure. If the proton attached to C2 in 1,1,2-tribromopropane is coupled with the protons on C1 (J = 3.6 Hz) and C3 (J = 6.8), the tree diagram of the C2 proton is shown below.

Which C4H9Br compound gives a doublet at approximately 3.3 ppm in the 1H NMR spectrum?

Which of the following is not true regarding 1H NMR spectroscopy?

Covalent Bonding and Shapes of Molecules

Alkanes and Cycloalkanes

Stereoisomerism and Chirality

Acids and Bases

Alkenes: Bonding, Nomenclature, and Properties

Reactions of Alkenes

Alkynes

Haloalkanes, Halogenation, and Radical Reactions

Nucleophilic Substitution and Beta-Elimination

Alcohols

Ethers, Epoxides, and Sulfides

Infrared Spectroscopy

Mass Spectrometry

An Introduction to Organometallic Compounds

Aldehydes and Ketones

Carboxylic Acids

Functional Derivatives of Carboxylic Acids

Enolate Anions and Enamines

Dienes, Conjugated Systems, and Pericyclic Reactions

Benzene and the Concept of Aromaticity

Reactions of Benzene and Its Derivatives

Amines

Catalytic Carbon-Carbon Bond Formation

Carbohydrates

Lipids

Amino Acids and Proteins

Nucleic Acids

Organic Polymer Chemistry

Filters

Identify the type of coupling that exists between the two protons in the following compound, given that the compound is asymmetrical.

The splitting of signals in the ¹H NMR spectrum provides information about the number of neighboring protons of each proton in the compound.

Identify the compound (C₄H₈O) that gives the following ¹H NMR spectrum.

For each of the compounds below tell how many signals you would expect the molecule to have in its normal, broadband hydrogen-decoupled ¹³C NMR spectra. Enter the numerical value in the blank provided to the left of the structure. -_______

Which of the following combinations of peaks appears in the ¹H NMR spectrum of butane?

Identify the compound (C₈H₁₀) that gives the following ¹H NMR spectrum.

Which of the protons in the following molecule appear furthest downfield in the ¹H NMR spectrum? $\mathrm{CH}_{3}-\mathrm{CH}_{2}-\mathrm{CH}_{2}-\mathrm{CH}_{2}-\mathrm{Cl}$ $\quad$ i $\quad$ $\quad$ $\quad$ ii $\quad$ $\quad$ iii $\quad$ $\quad$ iv

Consider the following structure. Answer the following questions by placing the appropriate number in the blank to the left. -_____The number of signals in the hydrogen-decoupled ¹³C NMR of this compound.

What is the splitting of the signal in the ¹H NMR spectrum for the methyl protons of ethane?

What is the hydrogen deficiency index for a compound with a molecular formula of C₁₀H₁₆O₂?

Which C₈H₁₀ compound gives the following ¹H NMR spectrum?

Which C₉H₁₀O compound gives the following ¹H NMR spectrum?

Which feature in the ¹H NMR spectrum provides information about the electronic environment of the protons in a compound?

Which C₄H₉Br compound gives a doublet at approximately 3.3 ppm in the ¹H NMR spectrum?

Which of the following is not true regarding ¹H NMR spectroscopy?