Question 1

In the molecular orbital model of benzene,how many  $\pi$-antibonding molecular orbitals are there?

Accepted Answer

A)  6 
B)  5 
C)  4 
D)  3 
E)  2 
A)  6 
B)  5 
C)  4 
D)  3 
E)  2

Question 2

When a benzene ring is used as a substituent,it is called a _________ group.

Accepted Answer

The answer of When a benzene ring is used as...

Question 3

How many different dichloronitrobenzenes are possible?

Accepted Answer

A)  8 
B)  7 
C)  6 
D)  5 
E)  4 
A)  8 
B)  7 
C)  6 
D)  5 
E)  4

Question 4

Of Hückel's requirements for aromatic character,only this one is waived in the case of certain compounds considered to be aromatic.

Accepted Answer

A)  The ring system must be planar. 
B)  The system must be monocyclic. 
C)  There must be (4n + 2) $\pi$ electrons. 
D)  The Hückel number of electrons must be completely delocalized. 
E)  None.All of these rules must apply in every case. 
A)  The ring system must be planar. 
B)  The system must be monocyclic. 
C)  There must be (4n + 2) $\pi$ electrons. 
D)  The Hückel number of electrons must be completely delocalized. 
E)  None.All of these rules must apply in every case.

Question 5

Which reagent(s)would serve as the basis for a simple chemical test that would distinguish between ethylbenzene and vinylcyclohexane?

Accepted Answer

A)  H2CrO4 
B)  LAH 
C)  NaBH4,H2O 
D)  O3/Zn,H+ 
E)  Two of the above 
A)  H2CrO4 
B)  LAH 
C)  NaBH4,H2O 
D)  O3/Zn,H+ 
E)  Two of the above

Question 6

Use the "polygon-in-circle" method to draw an MO diagram showing the pi-electron distribution pattern in the cycloheptatrienyl cation.How is this diagram useful in explaining the antiaromatic properties of this anion?

Accepted Answer

This MO diagram can be generated using t

Question 7

Which dibromobenzene can yield only one mononitro derivative?

Accepted Answer

A)  o-Dibromobenzene 
B)  m-Dibromobenzene 
C)  p-Dibromobenzene 
D)  More than one of these 
E)  None of these 
A)  o-Dibromobenzene 
B)  m-Dibromobenzene 
C)  p-Dibromobenzene 
D)  More than one of these 
E)  None of these

Question 8

Which compound would you NOT expect to be aromatic?

Accepted Answer

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

Question 9

Which of the following substances,formula C8H9Br,might exhibit the following 1H NMR spectrum ? 
triplet,$\delta$ 2.8
Triplet,$\delta$ 4.65
Multiplet,$\delta$ 7.2

Accepted Answer

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

Question 10

In theory,a single molecule of this compound will rotate plane-polarized light.

Accepted Answer

A)  Butylbenzene 
B)  Isobutylbenzene 
C)  sec-Butylbenzene 
D)  tert-Butylbenzene 
E)  None of these 
A)  Butylbenzene 
B)  Isobutylbenzene 
C)  sec-Butylbenzene 
D)  tert-Butylbenzene 
E)  None of these

Question 11

Cagelike molecules with the geometry of a truncated icosahedron are called ___________.

Accepted Answer

The answer of Cagelike molecules with the geometry of a...

Question 12

How many equivalent resonance structures can be written for the cycloheptatrienyl cation?

Accepted Answer

A)  3 
B)  4 
C)  5 
D)  6 
E)  7 
A)  3 
B)  4 
C)  5 
D)  6 
E)  7

Question 13

In which of the following compounds would the longest carbon-carbon bond(s)be found?

Accepted Answer

A)  2-Bromobenzaldehyde 
B)  Vinylbenzene 
C)  1,3,5-Heptatriene 
D)  2,4,6-Octatriene 
E)  2-Ethylbenzoic acid 
A)  2-Bromobenzaldehyde 
B)  Vinylbenzene 
C)  1,3,5-Heptatriene 
D)  2,4,6-Octatriene 
E)  2-Ethylbenzoic acid

Question 14

Phenol is the name commonly assigned to:

Accepted Answer

A)  Hydroxybenzene 
B)  Aminobenzene 
C)  Methylbenzene 
D)  Ethylbenzene 
E)  Methoxybenzene 
A)  Hydroxybenzene 
B)  Aminobenzene 
C)  Methylbenzene 
D)  Ethylbenzene 
E)  Methoxybenzene

Question 15

Which of the following would you expect to be antiaromatic?

Accepted Answer

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

Question 16

Benzene,while unusually unreactive with electrophiles,will react under certain conditions.However,when it does react,it does so by ___________ rather than by addition.

Accepted Answer

The answer of Benzene,while unusually unreactive with electrophiles,will react under...

Question 17

Monocyclic compounds with alternating single and double bonds are called __________.

Accepted Answer

The answer of Monocyclic compounds with alternating single and double...

Question 18

Consider the nitrogen atom in the molecules of pyrrole and pyrrolidine.Bearing in mind
that pyrrole exhibits aromatic properties,compare the hybridization of nitrogen in both
species,explaining why it must be different,although at first glance,it may appear
identical.

Accepted Answer

@#IMG-DLM& In pyrrole,the conjugated unsaturated r

Question 19

In the molecular orbital model of cyclobutadiene,how many non-bonding molecular orbitals are there?

Accepted Answer

A)  1 
B)  2 
C)  3 
D)  4 
E)  0 
A)  1 
B)  2 
C)  3 
D)  4 
E)  0

Question 20

Which of the following substances,formula C8H9Br,might exhibit the following 1H NMR spectrum ?
 triplet,$\delta$ 1.2
Quartet,$\delta$ 2.45
Multiplet,$\delta$ 7.4

Accepted Answer

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

Exam 14: Aromatic Compounds

In the molecular orbital model of benzene,how many π\piπ -antibonding molecular orbitals are there?

When a benzene ring is used as a substituent,it is called a _________ group.

How many different dichloronitrobenzenes are possible?

Of Hückel's requirements for aromatic character,only this one is waived in the case of certain compounds considered to be aromatic.

Which reagent(s)would serve as the basis for a simple chemical test that would distinguish between ethylbenzene and vinylcyclohexane?

Use the "polygon-in-circle" method to draw an MO diagram showing the pi-electron distribution pattern in the cycloheptatrienyl cation.How is this diagram useful in explaining the antiaromatic properties of this anion?

Which dibromobenzene can yield only one mononitro derivative?

Which compound would you NOT expect to be aromatic?

Which of the following substances,formula C8H9Br,might exhibit the following 1H NMR spectrum ? triplet, δ\deltaδ 2.8 Triplet, δ\deltaδ 4.65 Multiplet, δ\deltaδ 7.2

In theory,a single molecule of this compound will rotate plane-polarized light.

Cagelike molecules with the geometry of a truncated icosahedron are called ___________.

How many equivalent resonance structures can be written for the cycloheptatrienyl cation?

In which of the following compounds would the longest carbon-carbon bond(s)be found?

Phenol is the name commonly assigned to:

Which of the following would you expect to be antiaromatic?

Benzene,while unusually unreactive with electrophiles,will react under certain conditions.However,when it does react,it does so by ___________ rather than by addition.

Monocyclic compounds with alternating single and double bonds are called __________.

Consider the nitrogen atom in the molecules of pyrrole and pyrrolidine.Bearing in mind that pyrrole exhibits aromatic properties,compare the hybridization of nitrogen in both species,explaining why it must be different,although at first glance,it may appear identical.

In the molecular orbital model of cyclobutadiene,how many non-bonding molecular orbitals are there?

Which of the following substances,formula C8H9Br,might exhibit the following 1H NMR spectrum ? triplet, δ\deltaδ 1.2 Quartet, δ\deltaδ 2.45 Multiplet, δ\deltaδ 7.4

Carbon Compounds and Chemical Bonds

Representative Carbon Compounds: Functional Groups, Intermolecular Forces, and Infrared Ir Spectroscopy

An Introduction to Organic Reactions: Acids and Bases

Alkanes: Nomenclature, Conformational Analysis, and an Introduction to Synthesis

Stereochemistry: Chiral Molecules

Ionic Reactions - Nucleophilic Substitution and Elimination Reactions of Alkyl Halides

Alkenes and Alkynes I: Properties and Synthesis, Elimination Reactions of Alkyl Halides

Alkenes and Alkynes Ii: Addition Reactions

Nuclear Magnetic Resonance and Mass Spectrometry: Tools for Structure Determination

Radical Reactions

Alcohols and Ethers

Alcohols From Carbonyl Compounds Oxidation-Reduction and Organometallic Compounds

Conjugated Unsaturated Systems

Reactions of Aromatic Compounds

Aldehydes and Ketones I Nucleophilic Addition to the Carbonyl Group

Aldehydes and Ketones Ii Aldol Reactions

Carboxylic Acids and Their Derivatives Nucleophilic Addition - Elimination at the Acyl Carbon

Synthesis and Reactions of Beta-Dicarbonyl Compounds: More Chemistry of Enolate Ions

Amines

Phenols and Aryl Halides: Nucleophilic Aromatic Substitution

Carbohydrates

Lipids

Amino Acids and Proteins

Nucleic Acids and Protein Synthesis

Filters

In the molecular orbital model of benzene,how many $\pi$ -antibonding molecular orbitals are there?