Question 1

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

Accepted Answer

A) I = 3; II = 5; III = 5; IV = 4; V = 3 
B) I = 4; II = 5; III = 4; IV = 4; V = 3 
C) I = 4; II = 5; III = 5; IV = 4; V = 3 
D) I = 4; II = 5; III = 5; IV = 3; V = 4 
A) I = 3; II = 5; III = 5; IV = 4; V = 3 
B) I = 4; II = 5; III = 4; IV = 4; V = 3 
C) I = 4; II = 5; III = 5; IV = 4; V = 3 
D) I = 4; II = 5; III = 5; IV = 3; V = 4

Question 2

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 3

For each of the following compounds,indicate how many 13C NMR signals will be observed.

Accepted Answer

A) a: 4; b: 4; c: 7; d: 4 
B) a: 5; b: 4; c: 7; d: 3 
C) a: 4; b: 7; c: 7; d: 3 
D) a: 5; b: 4; c: 6; d: 5 
A) a: 4; b: 4; c: 7; d: 4 
B) a: 5; b: 4; c: 7; d: 3 
C) a: 4; b: 7; c: 7; d: 3 
D) a: 5; b: 4; c: 6; d: 5

Question 4

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

Question 5

An unknown compound X has the molecular formula C6H14O.Compound X shows a strong peak in its IR spectrum at 3000 cm-1.The 1H NMR spectral data of compound X is given below.What is the structure of compound X?

Accepted Answer

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

Question 6

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

Accepted Answer

A) I = 2; II = 4; III = 6 
B) I = 2; II = 4; III = 4 
C) I = 3; II = 3; III = 5 
D) I = 2; II = 4; III = 5 
A) I = 2; II = 4; III = 6 
B) I = 2; II = 4; III = 4 
C) I = 3; II = 3; III = 5 
D) I = 2; II = 4; III = 5

Question 7

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 8

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 9

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

Accepted Answer

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

Question 10

How many different kinds of 13C peaks will be seen?

Accepted Answer

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

Question 11

Into how many peaks will each of the circled protons be split? (Assume complete resolution of all NMR peaks is possible)

Accepted Answer

A) I = 3; II = 7; III = 4 
B) I = 2; II = 7; III = 4 
C) I = 2; II = 7; III = 3 
D) I = 2; II = 6; III = 4 
A) I = 3; II = 7; III = 4 
B) I = 2; II = 7; III = 4 
C) I = 2; II = 7; III = 3 
D) I = 2; II = 6; III = 4

Question 12

An unknown compound X has the molecular formula C6H14O.Compound X shows a peak in its IR spectrum at 3200-3600 cm-1.The 1H NMR spectral data for compound X is given below.What is the structure of compound X?

Accepted Answer

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

Question 13

Which compound does not give four sets of absorptions in its 1H NMR spectrum (i.e.,which compound does not have four unique hydrogens)?

Accepted Answer

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

Question 14

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 15

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

Accepted Answer

A) I = 4; II = 4; III = 4 
B) I = 4; II = 4; III = 5 
C) I = 3; II = 3; III = 5 
D) I = 3; II = 4; III = 5 
A) I = 4; II = 4; III = 4 
B) I = 4; II = 4; III = 5 
C) I = 3; II = 3; III = 5 
D) I = 3; II = 4; III = 5

Question 16

For each of the following compounds,indicate how many 13C NMR signals will be seen.

Accepted Answer

A) a: 3; b: 3; c: 5; d: 3 
B) a: 4; b: 3; c: 5; d: 3 
C) a: 3; b: 4; c: 5; d: 3 
D) a: 4; b: 3; c: 3; d: 3 
A) a: 3; b: 3; c: 5; d: 3 
B) a: 4; b: 3; c: 5; d: 3 
C) a: 3; b: 4; c: 5; d: 3 
D) a: 4; b: 3; c: 3; d: 3

Question 17

Which of the indicated protons absorbs further downfield?

Accepted Answer

A) HA 
B) HB 
C) HC 
D) HD 
A) HA 
B) HB 
C) HC 
D) HD

Question 18

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 19

An unknown compound X has the molecular formula C6H12O2.Compound X shows a strong peak in its IR spectrum at 1700 cm-1.The 1H NMR spectral data of compound X is given below.What is the structure of compound X?

Accepted Answer

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

Question 20

An unknown compound X has the empirical formula C3H6O and a molecular ion in its mass spectrum at 116.Compound X shows no IR absorption at 3200-3600 cm-1 but shows a peak at 1700 cm-1.The 1H NMR spectral data of X is shown below.What is the structure of compound X?

Accepted Answer

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

Exam 32: Spectroscopy C: Nuclear Magnetic Resonance Spectroscopy

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

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

For each of the following compounds,indicate how many 13C NMR signals will be observed.

Into how many peaks will the circled proton be split?

An unknown compound X has the molecular formula C6H14O.Compound X shows a strong peak in its IR spectrum at 3000 cm-1.The 1H NMR spectral data of compound X is given below.What is the structure of compound X?

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

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

Which of the indicated protons absorbs furthest downfield?

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

How many different kinds of 13C peaks will be seen?

Into how many peaks will each of the circled protons be split? (Assume complete resolution of all NMR peaks is possible)

An unknown compound X has the molecular formula C6H14O.Compound X shows a peak in its IR spectrum at 3200-3600 cm-1.The 1H NMR spectral data for compound X is given below.What is the structure of compound X?

Which compound does not give four sets of absorptions in its 1H NMR spectrum (i.e.,which compound does not have four unique hydrogens)?

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

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

For each of the following compounds,indicate how many 13C NMR signals will be seen.

Which of the indicated protons absorbs further downfield?

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

An unknown compound X has the molecular formula C6H12O2.Compound X shows a strong peak in its IR spectrum at 1700 cm-1.The 1H NMR spectral data of compound X is given below.What is the structure of compound X?

An unknown compound X has the empirical formula C3H6O and a molecular ion in its mass spectrum at 116.Compound X shows no IR absorption at 3200-3600 cm-1 but shows a peak at 1700 cm-1.The 1H NMR spectral data of X is shown below.What is the structure of compound X?

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 and Addition Reactions

Alkynes and Synthesis

Oxidation and Reduction

Radical Reactions

Conjugation,resonance,and Dienes

Benzene and Aromatic Compounds

Reactions of Aromatic Compounds

Introduction to Carbonyl Chemistry; Organometallic Reagents; Oxidation and Reduction

Aldehydes and Ketones - Nucleophilic Addition

Carboxylic Acids and the Acidity of the O-H Bond

Carboxylic Acids and Their Derivatives Nucleophilic Acyl Substitution

Substitution Reactions of Carbonyl Compounds at the a Carbon

Carbonyl Condensation Reactions

Amines

Carbon-Carbon Bond-Forming Reactions in Organic Synthesis

Pericyclic Reactions

Carbohydrates

Amino Acids and Proteins

Synthetic Polymers

Lipids

Spectroscopy A: Mass Spectrometry

Spectroscopy B: Infrared Spectroscopy

Filters

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

For each of the following compounds,indicate how many ¹³C NMR signals will be observed.

An unknown compound X has the molecular formula C₆H₁₄O.Compound X shows a strong peak in its IR spectrum at 3000 cm^-1.The ¹H NMR spectral data of compound X is given below.What is the structure of compound X?

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

How many different kinds of ¹³C peaks will be seen?

An unknown compound X has the molecular formula C₆H₁₄O.Compound X shows a peak in its IR spectrum at 3200-3600 cm^-1.The ¹H NMR spectral data for compound X is given below.What is the structure of compound X?

Which compound does not give four sets of absorptions in its ¹H NMR spectrum (i.e.,which compound does not have four unique hydrogens)?

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

For each of the following compounds,indicate how many ¹³C NMR signals will be seen.

An unknown compound X has the molecular formula C₆H₁₂O₂.Compound X shows a strong peak in its IR spectrum at 1700 cm^-1.The ¹H NMR spectral data of compound X is given below.What is the structure of compound X?

An unknown compound X has the empirical formula C₃H₆O and a molecular ion in its mass spectrum at 116.Compound X shows no IR absorption at 3200-3600 cm^-1 but shows a peak at 1700 cm^-1.The ¹H NMR spectral data of X is shown below.What is the structure of compound X?