Question 1

How many p orbital electrons are present in cyclopentadienyl anion?

Accepted Answer

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

Question 2

What is the major organic product obtained from the following reaction?

Accepted Answer

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

Question 3

What is the best choice of reagent to achieve the following reaction?

Accepted Answer

A)  H2SO4 
B)  NaOH, H2O 
C)  K2Cr2O7, H2SO4 
D)  LiAlH4 
A)  H2SO4 
B)  NaOH, H2O 
C)  K2Cr2O7, H2SO4 
D)  LiAlH4

Question 4

Which of the following statements is not true about the structure of benzene?

Accepted Answer

A)  six atomic 2p-orbitals overlap to form six p-molecular orbitals 
B)  there are three bonding p-molecular orbitals and three p-antibonding molecular orbitals 
C)  the ground state electronic configuration of benzene has six electrons in three p-bonding molecular orbitals 
D)  the bonds alternate in length around the ring 
A)  six atomic 2p-orbitals overlap to form six p-molecular orbitals 
B)  there are three bonding p-molecular orbitals and three p-antibonding molecular orbitals 
C)  the ground state electronic configuration of benzene has six electrons in three p-bonding molecular orbitals 
D)  the bonds alternate in length around the ring

Question 5

Which is the correct assignment of the names of the following substituted benzenes?

Accepted Answer

A)  1 = phenol; 2 = m-cresol; 3 = toluene 
B)  1 = m-cresol; 2 = resorcinol; 3 = m-xylene 
C)  1 = anisole; 2 = catechol; 3 = m-xylene 
D)  1 = m-cresol; 2 = anisole; 3 = cumene 
A)  1 = phenol; 2 = m-cresol; 3 = toluene 
B)  1 = m-cresol; 2 = resorcinol; 3 = m-xylene 
C)  1 = anisole; 2 = catechol; 3 = m-xylene 
D)  1 = m-cresol; 2 = anisole; 3 = cumene

Question 6

Which of the following statements is not true about the structure of benzene?

Accepted Answer

A)  the carbon-carbon bonds are all the same length 
B)  the structure rapidly transforms between two resonance contributors 
C)  the structure is an average of two resonance contributors 
D)  the ring of six carbon atoms is planar 
A)  the carbon-carbon bonds are all the same length 
B)  the structure rapidly transforms between two resonance contributors 
C)  the structure is an average of two resonance contributors 
D)  the ring of six carbon atoms is planar

Question 7

What is the correct assignment of the names of the following heterocycles?

Accepted Answer

A)  1 = pyrrole; 2 = thiophene; 3 = pyridine 
B)  1 = thiophene; 2 = furan; 3 = pyrrole 
C)  1 = pyridine; 2 = thiophene; 3 = furan 
D)  1 = pyridine; 2 = thiophene; 3 = pyrrole 
A)  1 = pyrrole; 2 = thiophene; 3 = pyridine 
B)  1 = thiophene; 2 = furan; 3 = pyrrole 
C)  1 = pyridine; 2 = thiophene; 3 = furan 
D)  1 = pyridine; 2 = thiophene; 3 = pyrrole

Question 8

Provide a brief explanation of why furan (below) is aromatic. Your answer should identify the hybridization of the oxygen atom and account for which electrons are in the pi system.

Accepted Answer

The oxygen is sp² hybridized. One lone p

Question 9

Which of the following has the compounds shown in the correct order of decreasing acidity (i.e., more acidic > less acidic)?

Accepted Answer

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

Question 10

Which orbitals contain the lone pairs on the nitrogen atoms labeled i and ii in the imidazole ring?

Accepted Answer

A)  i = sp2;; ii = sp3 
B)  i = p;; ii = sp3 
C)  i = p;; ii = sp3. 
D)  i = p;; ii = sp2 
A)  i = sp2;; ii = sp3 
B)  i = p;; ii = sp3 
C)  i = p;; ii = sp3. 
D)  i = p;; ii = sp2

Question 11

What is the major organic product obtained from the following reaction?

Accepted Answer

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

Question 12

What is the major organic product obtained from the following reaction?

Accepted Answer

The answer of What is the major organic product obtained...

Question 13

Which orbital contains the lone pair on the nitrogen atom of pyrrole?

Accepted Answer

A)  s 
B)  p 
C)  sp 
D)  sp2 
A)  s 
B)  p 
C)  sp 
D)  sp2

Question 14

Which of the following is true about [10]annulene?

Accepted Answer

A)  [10]annulene is planar 
B)  [10]annulene is nonaromatic 
C)  [10]annulene undergoes addition reactions similar to simple alkenes 
D)  [10]annulene has 10 pi electrons 
A)  [10]annulene is planar 
B)  [10]annulene is nonaromatic 
C)  [10]annulene undergoes addition reactions similar to simple alkenes 
D)  [10]annulene has 10 pi electrons

Question 15

What is the hybridization of the oxygen atom of furan?

Accepted Answer

A)  s 
B)  sp 
C)  sp2 
D)  sp3 
A)  s 
B)  sp 
C)  sp2 
D)  sp3

Question 16

Which of the following has the compounds shown in the correct order of decreasing acidity (i.e., more acidic > less acidic)?

Accepted Answer

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

Question 17

What is the best choice of reagent to achieve the following reaction?

Accepted Answer

A)  H2SO4 
B)  NaOH, H2O 
C)  K2Cr2O7, H2SO4 
D)  H2/Pd 
A)  H2SO4 
B)  NaOH, H2O 
C)  K2Cr2O7, H2SO4 
D)  H2/Pd

Question 18

Provide a brief explanation of why the cyclopentadienyl anion (below) is aromatic. Your answer should identify the hybridization of each carbon atom and account for which electrons are in the pi system.

Accepted Answer

The all five carbons are sp² hybridized.

Question 19

Which of the following compounds is antiaromatic?

Accepted Answer

A)  ethane 
B)  cyclobutadiene 
C)  benzene 
D)  cyclooctatetraene 
A)  ethane 
B)  cyclobutadiene 
C)  benzene 
D)  cyclooctatetraene

Exam 21: Benzene and the Concept of Aromaticity

How many p orbital electrons are present in cyclopentadienyl anion?

What is the major organic product obtained from the following reaction?

What is the best choice of reagent to achieve the following reaction?

Which of the following statements is not true about the structure of benzene?

Which is the correct assignment of the names of the following substituted benzenes?

Which of the following statements is not true about the structure of benzene?

What is the correct assignment of the names of the following heterocycles?

Provide a brief explanation of why furan (below) is aromatic. Your answer should identify the hybridization of the oxygen atom and account for which electrons are in the pi system.

Which of the following has the compounds shown in the correct order of decreasing acidity (i.e., more acidic > less acidic)?

Which orbitals contain the lone pairs on the nitrogen atoms labeled i and ii in the imidazole ring?

What is the major organic product obtained from the following reaction?

What is the major organic product obtained from the following reaction?

Which orbital contains the lone pair on the nitrogen atom of pyrrole?

Which of the following is true about [10]annulene?

What is the hybridization of the oxygen atom of furan?

Which of the following has the compounds shown in the correct order of decreasing acidity (i.e., more acidic > less acidic)?

What is the best choice of reagent to achieve the following reaction?

Provide a brief explanation of why the cyclopentadienyl anion (below) is aromatic. Your answer should identify the hybridization of each carbon atom and account for which electrons are in the pi system.

Which of the following compounds is antiaromatic?

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

Nuclear Magnetic Resonance 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

Reactions of Benzene and Its Derivatives

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