Question 1

Nuclear magnetic resonance spectroscopy provides information about a molecule's:

Accepted Answer

A)  conjugated pi electron system. 
B)  size and formula. 
C)  carbon-hydrogen framework. 
D)  functional groups. 
A)  conjugated pi electron system. 
B)  size and formula. 
C)  carbon-hydrogen framework. 
D)  functional groups.

Question 2

The following questions pertain to the display of NMR spectra. Match a term to each description below.
-The vertical axis of spectrum displays the _____ of the signal.

Accepted Answer

A) TMS 
B) high-field or upfield side 
C) MHz 
D) delta (δ) 
E) low-field or downfield side
F)chemical shift
G)intensity 
A) TMS 
B) high-field or upfield side 
C) MHz 
D) delta (δ) 
E) low-field or downfield side
F)chemical shift
G)intensity

Question 3

For each of the compounds below tell how many signals you would expect the molecule to have in its normal, broadband decoupled S1U1P113S1S1P0C NMR spectra.
-Arrange the following compounds in order of increasing number of signals in a 13C NMR spectrum.

Accepted Answer

Question 4

Which of the following combinations of peaks appears in the 1H NMR spectrum of 2-methylpropane?

Accepted Answer

A)  two singlets 
B)  a singlet and a nonet 
C)  a singlet and a decet 
D)  a doublet and a decet 
A)  two singlets 
B)  a singlet and a nonet 
C)  a singlet and a decet 
D)  a doublet and a decet

Question 5

The following questions pertain to the display of NMR spectra. Match a term to each description below.
-The exact place on the spectrum at which a nucleus absorbs is called its _____.

Accepted Answer

A) TMS 
B) high-field or upfield side 
C) MHz 
D) delta (δ) 
E) low-field or downfield side
F)chemical shift
G)intensity 
A) TMS 
B) high-field or upfield side 
C) MHz 
D) delta (δ) 
E) low-field or downfield side
F)chemical shift
G)intensity

Question 6

How many sets of equivalent protons are there in hexane, 2-methylhexane, and 3-methylhexane, respectively?

Accepted Answer

The answer of How many sets of equivalent protons are...

Question 7

Answer the following question(s) for the compound whose S1U1P11S1S1P0H NMR spectra is shown below.
CS1U1B14S1U1B0HS1U1B18S1U1B0O   (Spectrum obtained from: SDBSWeb: http://www.aist.go.jp/RIODB/SDBS/)
-Refer to instructions. Propose a structure for this compound.

Accepted Answer

butan-2-on

Question 8

How many positive and negative peaks appear in the DEPT-135 spectrum of 2,4-dimethylpentane?

Accepted Answer

A)  two positive and one negative 
B)  three positive and two negative 
C)  four positive and three negative 
D)  six positive and one negative 
A)  two positive and one negative 
B)  three positive and two negative 
C)  four positive and three negative 
D)  six positive and one negative

Question 9

Refer to the structure of 3-methylbutan-2-one below to answer the following question(s).  
-Refer to instructions. What is the splitting pattern for the hydrogens in 3-methylbutan-2-one labeled A, B, and C, respectively?

Accepted Answer

A)  singlet, singlet, singlet 
B)  singlet, septet, quartet 
C)  singlet, septet, doublet 
D)  singlet, septet, doublet, doublet 
A)  singlet, singlet, singlet 
B)  singlet, septet, quartet 
C)  singlet, septet, doublet 
D)  singlet, septet, doublet, doublet

Question 10

Predict the splitting patterns you would expect for each proton in the molecules below:
-Predict:

Accepted Answer

The answer of Predict the splitting patterns you would expect...

Question 11

How many signals appear in the broadband-decoupled 13C NMR spectrum of 1,2-dibromobenzene?

Accepted Answer

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

Question 12

Refer to the structure of 3-methylbutan-2-one below to answer the following question(s).  
-A compound with the molecular formula C5H12O produces only two singlets in the 1H NMR spectrum.
a)Propose a structure for this compound.
b)How many signals would be present in the 13C NMR for this structure?

Accepted Answer

Question 13

Predict the splitting patterns you would expect for each proton in the molecules below:
-Predict:

Accepted Answer

The answer of Predict the splitting patterns you would expect...

Question 14

Which of the following combinations of peaks appears in the 1H NMR spectrum of diethyl ether, CH3CH2OCH2CH3?

Accepted Answer

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

Question 15

For each of the compounds below tell how many signals you would expect the molecule to have in its normal, broadband decoupled S1U1P113S1S1P0C NMR spectra.
-Number of signals:

Accepted Answer

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

Question 16

Which of the following compounds gives a 1H NMR spectrum consisting of only two singlets?

Accepted Answer

A)  CH3OCH2CH2OCH2CH3 
B)  CH3OCH2CH2CH2CH2OH 
C)  CH3OC(CH3)2OCH3 
D)  CH3OCH2CH(CH3)OCH3 
A)  CH3OCH2CH2OCH2CH3 
B)  CH3OCH2CH2CH2CH2OH 
C)  CH3OC(CH3)2OCH3 
D)  CH3OCH2CH(CH3)OCH3

Question 17

For each of the compounds below tell how many signals you would expect the molecule to have in its normal, broadband decoupled S1U1P113S1S1P0C NMR spectra.
-Number of signals:

Accepted Answer

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

Question 18

Answer the following question(s) for the compound whose S1U1P11S1S1P0H NMR spectra is shown below.
CS1U1B14S1U1B0HS1U1B18S1U1B0O   (Spectrum obtained from: SDBSWeb: http://www.aist.go.jp/RIODB/SDBS/)
-Refer to instructions. Describe each signal in terms of its integration, splitting and chemical shift.

Accepted Answer

The signals at 1.05 and 2.45 δ are chara

Question 19

For each of the compounds below tell how many signals you would expect the molecule to have in its normal, broadband decoupled S1U1P113S1S1P0C NMR spectra.
-Which of the following would produce only singlets in an 1H NMR spectrum? A   B   C   D   ​

Accepted Answer

A)  A 
B)  B 
C)  C 
D)  D 
E)  all of these produce only singlets 
A)  A 
B)  B 
C)  C 
D)  D 
E)  all of these produce only singlets

Question 20

How many signals appear in the broadband-decoupled 13C NMR spectrum of 1,3-dibromobenzene?

Accepted Answer

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

Exam 11: Structure Determination: Nuclear Magnetic Resonance Spectroscopy

Nuclear magnetic resonance spectroscopy provides information about a molecule's:

The following questions pertain to the display of NMR spectra. Match a term to each description below. -The vertical axis of spectrum displays the _____ of the signal.

For each of the compounds below tell how many signals you would expect the molecule to have in its normal, broadband decoupled 13C NMR spectra. -Arrange the following compounds in order of increasing number of signals in a 13C NMR spectrum.

Which of the following combinations of peaks appears in the 1H NMR spectrum of 2-methylpropane?

The following questions pertain to the display of NMR spectra. Match a term to each description below. -The exact place on the spectrum at which a nucleus absorbs is called its _____.

How many sets of equivalent protons are there in hexane, 2-methylhexane, and 3-methylhexane, respectively?

Answer the following question(s) for the compound whose 1H NMR spectra is shown below. C4H8O (Spectrum obtained from: SDBSWeb: http://www.aist.go.jp/RIODB/SDBS/) -Refer to instructions. Propose a structure for this compound.

How many positive and negative peaks appear in the DEPT-135 spectrum of 2,4-dimethylpentane?

Refer to the structure of 3-methylbutan-2-one below to answer the following question(s). -Refer to instructions. What is the splitting pattern for the hydrogens in 3-methylbutan-2-one labeled A, B, and C, respectively?

Predict the splitting patterns you would expect for each proton in the molecules below: -Predict:

How many signals appear in the broadband-decoupled 13C NMR spectrum of 1,2-dibromobenzene?

Refer to the structure of 3-methylbutan-2-one below to answer the following question(s). -A compound with the molecular formula C5H12O produces only two singlets in the 1H NMR spectrum. a)Propose a structure for this compound. b)How many signals would be present in the 13C NMR for this structure?

Predict the splitting patterns you would expect for each proton in the molecules below: -Predict:

Which of the following combinations of peaks appears in the 1H NMR spectrum of diethyl ether, CH3CH2OCH2CH3?

For each of the compounds below tell how many signals you would expect the molecule to have in its normal, broadband decoupled 13C NMR spectra. -Number of signals:

Which of the following compounds gives a 1H NMR spectrum consisting of only two singlets?

For each of the compounds below tell how many signals you would expect the molecule to have in its normal, broadband decoupled 13C NMR spectra. -Number of signals:

Answer the following question(s) for the compound whose 1H NMR spectra is shown below. C4H8O (Spectrum obtained from: SDBSWeb: http://www.aist.go.jp/RIODB/SDBS/) -Refer to instructions. Describe each signal in terms of its integration, splitting and chemical shift.

For each of the compounds below tell how many signals you would expect the molecule to have in its normal, broadband decoupled 13C NMR spectra. -Which of the following would produce only singlets in an 1H NMR spectrum? A B C D ​

How many signals appear in the broadband-decoupled 13C NMR spectrum of 1,3-dibromobenzene?

Structure and Bonding

Polar Covalent Bonds; Acids and Bases

Organic Compounds: Alkanes and Their Stereochemistry

Organic Compounds: Cycloalkanes and Their Stereochemistry

Stereochemistry at Tetrahedral Centers

An Overview of Organic Reactions

Alkenes and Alkynes

Reactions of Alkenes and Alkynes

Aromatic Compounds

Structure Determination: Mass Spectrometry, Infrared Spectroscopy, and Ultraviolet Spectroscopy

Structure Determination: Mass Spectrometry, Infrared Spectroscopy, and Ultraviolet Spectroscopy

Organohalides: Nucleophilic Substitutions and Eliminations

Alcohols, Phenols, and Thiols; Ethers and Sulfides

Aldehydes and Ketones: Nucleophilic Addition Reactions

Carboxylic Acids and Nitriles

Carboxylic Acid Derivatives: Nucleophilic Acyl Substitution Reactions

Carbonyl Alpha-Substitution and Condensation Reactions

Amines and Heterocycles

Biomolecules: Amino Acids, Peptides, and Proteins

Amino Acid Metabolism

Biomolecules: Carbohydrates

Carbohydrate Metabolism

Biomolecules: Lipids and Their Metabolism

Biomolecules: Nucleic Acids and Their Metabolism

Orbitals and Organic Chemistry: Pericyclic Reactionse

Synthetic Polymerse

Filters

For each of the compounds below tell how many signals you would expect the molecule to have in its normal, broadband decoupled ¹³C NMR spectra. -Arrange the following compounds in order of increasing number of signals in a ¹³C NMR spectrum.

Which of the following combinations of peaks appears in the ¹H NMR spectrum of 2-methylpropane?

Answer the following question(s) for the compound whose ¹H NMR spectra is shown below. C₄H₈O (Spectrum obtained from: SDBSWeb: http://www.aist.go.jp/RIODB/SDBS/) -Refer to instructions. Propose a structure for this compound.

How many signals appear in the broadband-decoupled ¹³C NMR spectrum of 1,2-dibromobenzene?

Which of the following combinations of peaks appears in the ¹H NMR spectrum of diethyl ether, CH₃CH₂OCH₂CH₃?

For each of the compounds below tell how many signals you would expect the molecule to have in its normal, broadband decoupled ¹³C NMR spectra. -Number of signals:

Which of the following compounds gives a ¹H NMR spectrum consisting of only two singlets?

For each of the compounds below tell how many signals you would expect the molecule to have in its normal, broadband decoupled ¹³C NMR spectra. -Number of signals:

Answer the following question(s) for the compound whose ¹H NMR spectra is shown below. C₄H₈O (Spectrum obtained from: SDBSWeb: http://www.aist.go.jp/RIODB/SDBS/) -Refer to instructions. Describe each signal in terms of its integration, splitting and chemical shift.

For each of the compounds below tell how many signals you would expect the molecule to have in its normal, broadband decoupled ¹³C NMR spectra. -Which of the following would produce only singlets in an ¹H NMR spectrum? A B C D

How many signals appear in the broadband-decoupled ¹³C NMR spectrum of 1,3-dibromobenzene?