Question 1

Which of the following compounds would give rise to a 13C spectrum with 6 peaks?

Accepted Answer

A) I 
B) II 
C) III 
D) IV 
A) I 
B) II 
C) III 
D) IV B

Question 2

How many different kinds of protons are present in each of the following compounds?

Accepted Answer

A) I = 2; II = 3; III = 4. 
B) I = 2; II = 3; III = 3. 
C) I = 3; II = 3; III = 3. 
D) I = 3; II = 3; III = 4. 
A) I = 2; II = 3; III = 4. 
B) I = 2; II = 3; III = 3. 
C) I = 3; II = 3; III = 3. 
D) I = 3; II = 3; III = 4. C

Question 3

Into how many peaks will the circled proton be split?

Accepted Answer

A) 5 
B) 6 
C) 7 
D) 8 
A) 5 
B) 6 
C) 7 
D) 8 C

Question 4

How many different kinds of protons are present in each of the following compounds?

Accepted Answer

A) a: 5; b: 6 
B) a: 5; b: 5 
C) a: 4; b: 6 
D) a: 4; b: 5 
A) a: 5; b: 6 
B) a: 5; b: 5 
C) a: 4; b: 6 
D) a: 4; b: 5

Question 5

Compound X has a molecular formula C8H10 and gives the 1H NMR spectrum below.What is the structure of X?

Accepted Answer

A) A 
B) B 
C) C 
D) D 
A) A 
B) B 
C) C 
D) D

Question 6

What effect does increasing the operating frequency of a 1H NMR spectrum have on the frequency of an absorption in Hz?

Accepted Answer

A) Frequency of an absorption in Hz will also increase. 
B) Frequency of an absorption in Hz will decrease. 
C) Frequency of an absorption in Hz will remain the same. 
D) It is not possible to predict the change in frequency of an absorption in Hz. 
A) Frequency of an absorption in Hz will also increase. 
B) Frequency of an absorption in Hz will decrease. 
C) Frequency of an absorption in Hz will remain the same. 
D) It is not possible to predict the change in frequency of an absorption in Hz.

Question 7

How could spectroscopy be used to distinguish between the following compounds?

Accepted Answer

A) Compound A has a triplet in its 1H NMR spectrum at 1.0 ppm. 
B) Compound B has a peak at 3200-3500 cm-1 in its IR spectrum. 
C) Compound A has a peak in its IR spectrum at 2900 cm-1. 
D) Compound A has a triplet in its 1H NMR spectrum at 1.0 ppm and compound B has a peak at 3200-3500 cm-1 in its IR spectrum. 
A) Compound A has a triplet in its 1H NMR spectrum at 1.0 ppm. 
B) Compound B has a peak at 3200-3500 cm-1 in its IR spectrum. 
C) Compound A has a peak in its IR spectrum at 2900 cm-1. 
D) Compound A has a triplet in its 1H NMR spectrum at 1.0 ppm and compound B has a peak at 3200-3500 cm-1 in its IR spectrum.

Question 8

Which of the indicated protons in the molecules below would absorb furthest downfield in a 1H NMR spectrum?

Accepted Answer

A) I 
B) II 
C) III 
D) IV 
A) I 
B) II 
C) III 
D) IV

Question 9

Which of the indicated protons would absorb furthest downfield in a 1H NMR spectrum?

Accepted Answer

A) I 
B) II 
C) III 
D) IV 
A) I 
B) II 
C) III 
D) IV

Question 10

An unknown compound A has the molecular formula C12H16O.Compound A absorbs strongly in the IR at 1700 cm-1.The NMR spectral data for compound A are given below.What is the structure of compound A?

Accepted Answer

A) I 
B) II 
C) III 
D) IV 
A) I 
B) II 
C) III 
D) IV

Question 11

Which of the indicated protons absorbs furthest downfield?

Accepted Answer

A) Ha 
B) Hb 
C) Hc 
D) Hd 
A) Ha 
B) Hb 
C) Hc 
D) Hd

Question 12

Which of the following statements is true about electromagnetic radiation?

Accepted Answer

A) All molecules absorb electromagnetic radiation at some frequency. 
B) Frequency is directly proportional to wavelength. 
C) NMR uses the microwave region of the electromagnetic spectrum. 
D) The radio frequency region of the electromagnetic spectrum has the largest energy per photon. 
E) Energy is inversely proportional to frequency. 
A) All molecules absorb electromagnetic radiation at some frequency. 
B) Frequency is directly proportional to wavelength. 
C) NMR uses the microwave region of the electromagnetic spectrum. 
D) The radio frequency region of the electromagnetic spectrum has the largest energy per photon. 
E) Energy is inversely proportional to frequency.

Question 13

How many different kinds of protons are present in each of the following compounds?

Accepted Answer

A) I = 4; II = 3; III = 1. 
B) I = 4; II = 4; III = 1. 
C) I = 4; II = 4; III = 2. 
D) I = 3; II = 3; III = 1. 
A) I = 4; II = 3; III = 1. 
B) I = 4; II = 4; III = 1. 
C) I = 4; II = 4; III = 2. 
D) I = 3; II = 3; III = 1.

Question 14

Which of the labeled protons absorbs furthest upfield in the 1H NMR spectrum?

Accepted Answer

A) Ha 
B) Hb 
C) Hc 
D) Hd 
A) Ha 
B) Hb 
C) Hc 
D) Hd

Question 15

Into how many peaks will each of the circled protons be split?

Accepted Answer

A) I = 3; II = 8; III = 1; IV = 4; V = 3. 
B) I = 9; II = 8; III = 2; IV = 4; V = 4. 
C) I = 4; II = 8; III = 2; IV = 4; V = 5. 
D) I = 4; Ii = 7; III = 2; IV = 4; V = 3. 
A) I = 3; II = 8; III = 1; IV = 4; V = 3. 
B) I = 9; II = 8; III = 2; IV = 4; V = 4. 
C) I = 4; II = 8; III = 2; IV = 4; V = 5. 
D) I = 4; Ii = 7; III = 2; IV = 4; V = 3.

Question 16

How many different kinds of protons are present in each of the following compounds?

Accepted Answer

A) I = 6; II = 5; III = 3. 
B) I = 7; II = 5; III = 3. 
C) I = 7; II = 6; III = 3. 
D) I = 6; II = 6; III = 3. 
A) I = 6; II = 5; III = 3. 
B) I = 7; II = 5; III = 3. 
C) I = 7; II = 6; III = 3. 
D) I = 6; II = 6; III = 3.

Question 17

How many peaks would be observed for each of the circled protons in the compounds below?

Accepted Answer

A) I = 6; II = 2; III = 3. 
B) I = 7; II = 3; III = 3. 
C) I = 7; II = 1; III = 3. 
D) I = 7; II = 2; III = 3. 
A) I = 6; II = 2; III = 3. 
B) I = 7; II = 3; III = 3. 
C) I = 7; II = 1; III = 3. 
D) I = 7; II = 2; III = 3.

Question 18

What is the relationship between Ha and Hb in the following compound?

Accepted Answer

A) Homotopic 
B) Enantiotopic 
C) Diastereotopic 
D) Mesotopic 
A) Homotopic 
B) Enantiotopic 
C) Diastereotopic 
D) Mesotopic

Question 19

Which of the following compounds does not show only one signal in its 1H NMR spectrum?

Accepted Answer

A) I 
B) II 
C) III 
D) IV 
A) I 
B) II 
C) III 
D) IV

Question 20

An unknown compound A has the molecular formula C7H14O2.Compound A absorbs strongly in the IR at 1700 cm-1.The 1H NMR spectral data for compound A are given below.What is the structure of compound A?

Accepted Answer

A) I 
B) II 
C) III 
D) IV 
A) I 
B) II 
C) III 
D) IV

Exam 14: Nuclear Magnetic Resonance Spectroscopy

Which of the following compounds would give rise to a 13C spectrum with 6 peaks?

How many different kinds of protons are present in each of the following compounds?

Into how many peaks will the circled proton be split?

How many different kinds of protons are present in each of the following compounds?

Compound X has a molecular formula C8H10 and gives the 1H NMR spectrum below.What is the structure of X?

What effect does increasing the operating frequency of a 1H NMR spectrum have on the frequency of an absorption in Hz?

How could spectroscopy be used to distinguish between the following compounds?

Which of the indicated protons in the molecules below would absorb furthest downfield in a 1H NMR spectrum?

Which of the indicated protons would absorb furthest downfield in a 1H NMR spectrum?

An unknown compound A has the molecular formula C12H16O.Compound A absorbs strongly in the IR at 1700 cm-1.The NMR spectral data for compound A are given below.What is the structure of compound A?

Which of the indicated protons absorbs furthest downfield?

Which of the following statements is true about electromagnetic radiation?

How many different kinds of protons are present in each of the following compounds?

Which of the labeled protons absorbs furthest upfield in the 1H NMR spectrum?

Into how many peaks will each of the circled protons be split?

How many different kinds of protons are present in each of the following compounds?

How many peaks would be observed for each of the circled protons in the compounds below?

What is the relationship between Ha and Hb in the following compound?

Which of the following compounds does not show only one signal in its 1H NMR spectrum?

An unknown compound A has the molecular formula C7H14O2.Compound A absorbs strongly in the IR at 1700 cm-1.The 1H NMR spectral data for compound A are given below.What is the structure of compound A?

Structure and Bonding

Acids and Bases

Introduction to Organic Molecules and Functional Groups

Alkanes

Stereochemistry

Understanding Organic Reactions

Alkyl Halides and Nucleophilic Substitution

Alkyl Halides and Elimination Reactions

Alcohols, Ethers, and Related Compounds

Alkenes

Alkynes

Oxidation and Reduction

Mass Spectrometry and Infrared Spectroscopy

Radical Reactions

Conjugation, Resonance, and Dienes

Benzene and Aromatic Compounds

Reactions of Aromatic Compounds

Carboxylic Acids and the Acidity of the O-H Bond

Introduction to Carbonyl Chemistry;

Aldehydes and Ketones Nucleophilic Addition

Carboxylic Acids and Derivatives

Substitution Reactions of Carbonyl Compounds at the Alpha-Carbon

Carbonyl Condensation Reactions

Amines

Carbon-Carbon Bond Forming Reactions in Organic Synthesis

Pericyclic Reactions

Carbohydrates

Amino Acids and Proteins

Synthetic Polymers

Lipids

Filters

Which of the following compounds would give rise to a ¹³C spectrum with 6 peaks?

Compound X has a molecular formula C₈H₁₀ and gives the ¹H NMR spectrum below.What is the structure of X?

What effect does increasing the operating frequency of a ¹H NMR spectrum have on the frequency of an absorption in Hz?

Which of the indicated protons in the molecules below would absorb furthest downfield in a ¹H NMR spectrum?

Which of the indicated protons would absorb furthest downfield in a ¹H NMR spectrum?

An unknown compound A has the molecular formula C₁₂H₁₆O.Compound A absorbs strongly in the IR at 1700 cm^-1.The NMR spectral data for compound A are given below.What is the structure of compound A?

Which of the labeled protons absorbs furthest upfield in the ¹H NMR spectrum?

What is the relationship between H_a and H_b in the following compound?

Which of the following compounds does not show only one signal in its ¹H NMR spectrum?

An unknown compound A has the molecular formula C₇H₁₄O₂.Compound A absorbs strongly in the IR at 1700 cm^-1.The ¹H NMR spectral data for compound A are given below.What is the structure of compound A?