Question 1

Which molecule would be expected to have the higher absorption wavelength?

Accepted Answer

A)  A because it's more conjugated
B)  A because it's less conjugated
C)  B because it's more conjugated
D)  B because it's less conjugatedE) All of the above
F) B) and C)

Question 2

Increased conjugation leads to an increase in absorption wavelength.

Accepted Answer

A) True 
 B)False

Question 3

Which molecule shown below would you expect to have the larger dipole moment.Draw resonance structures using electron flow arrows for both molecules to show why.

Accepted Answer

Initially,both A and B are non-aromatic....

Question 4

_______________ circles are a method of mapping out aromatic orbital diagrams.

Accepted Answer

The answer of _______________ circles are a method of mapping...

Question 5

Only ð electrons contribute towards aromaticity.

Accepted Answer

A) True 
 B)False

Question 6

The following molecule shown below is Lipitor,a drug prescribed to lower cholesterol levels.How many aromatic rings does it contain,how many ð electron pairs are part of its conjugated system,and how many atoms are part of its conjugated system?

Accepted Answer

4 aromatic...

Question 7

Benzyne (shown below)is a highly reactive yet still aromatic derivative of benzene.It is planar and cyclic,but has eight ð electrons instead of six.Explain how it is still aromatic yet but still defies Hückel's rule.

Accepted Answer

Hückel's rule represents ð electrons in ...

Question 8

How many nodal planes does the following representation of benzene have?

Accepted Answer

A)  0
B)  1
C)  2
D)  3E) A) and D)
F) B) and C)

Question 9

Which of the following best describes the following molecule?

Accepted Answer

A)  aromatic
B)  anti-aromatic
C)  non-aromatic
D)  somewhat aromaticE) A) and B)
F) A) and C)

Question 10

In the aromatic compound resonance form shown below,which heteroatoms are contributing lone pairs towards aromaticity?

Accepted Answer

A)  nitrogen only
B)  oxygen only
C)  both nitrogen and oxygen
D)  neither nitrogen or oxygenE) A) and B)
F) C) and D)

Question 11

How many ð electron pairs are in the following molecule of benzamide?

Accepted Answer

A)  3
B)  4
C)  5
D)  6E) None of the above
F) A) and B)

Question 12

Compared to ethene,butadiene would be expected to absorb light with which of the following properties?

Accepted Answer

A)  higher wavelength and higher energy
B)  higher wavelength and lower energy
C)  lower wavelength and higher energy
D)  lower wavelength and lower energyE) A) and C)
F) A) and D)

Question 13

Which of the following is an accurate description of benzene?

Accepted Answer

A)  There are two distinct structures in equilibrium.
B)  All the carbon-carbon bonds are the same length.
C)  Some carbon-carbon bonds are longer than others.
D)  There are distinct single and double bonds.E) C) and D)
F) A) and D)

Question 14

Which of the following best describes double bonds in aromatic systems?

Accepted Answer

A)  They are more susceptible to hydrogenation than non-aromatic double bonds.
B)  They are less susceptible to hydrogenation than double bonds.
C)  They are equally susceptible to hydrogenation when compared to non-aromatic double bonds.
D)  There is no difference between an aromatic and non-aromatic double bond.E) All of the above
F) A) and D)

Question 15

A molecule that is anti-aromatic has _______________ electrons in its conjugated ring system.

Accepted Answer

The answer of A molecule that is anti-aromatic has _______________...

Question 16

Aromatic double bonds tend to be _______________ stable than their corresponding non-aromatic double bonds.

Accepted Answer

The answer of Aromatic double bonds tend to be _______________...

Question 17

Amide bonds undergo free rotation at room temperature.

Accepted Answer

A) True 
 B)False

Question 18

A molecule must be planar to be considered aromatic.

Accepted Answer

A) True 
 B)False

Question 19

The larger the difference in energy between the HOMO and LUMO,the larger the wavelength of light a molecule will absorb.

Accepted Answer

A) True 
 B)False

Question 20

Which of the following is NOT a criterion for aromaticity?

Accepted Answer

A)  be cyclic and planar
B)  have a p-orbital on all participating ring atoms
C)  have 4n+2 number of delocalized ð electrons
D)  have an even number of atoms involved in the aromatic systemE) A) and B)
F) All of the above

Exam 9: Conjugation and Aromaticity

Only ð electrons contribute towards aromaticity.

Correct AnswerverifiedShow Answer

Aromatic double bonds tend to be _______________ stable than their corresponding non-aromatic double bonds.

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How many nodal planes does the following representation of benzene have?

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Compared to ethene,butadiene would be expected to absorb light with which of the following properties?

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The larger the difference in energy between the HOMO and LUMO,the larger the wavelength of light a molecule will absorb.

Correct AnswerverifiedShow Answer

Which molecule shown below would you expect to have the larger dipole moment.Draw resonance structures using electron flow arrows for both molecules to show why.

Correct AnswerverifiedInitially,both A and B are non-aromatic....View AnswerShow Answer

In the aromatic compound resonance form shown below,which heteroatoms are contributing lone pairs towards aromaticity?

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A molecule must be planar to be considered aromatic.

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Increased conjugation leads to an increase in absorption wavelength.

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A molecule that is anti-aromatic has _______________ electrons in its conjugated ring system.

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_______________ circles are a method of mapping out aromatic orbital diagrams.

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Which molecule would be expected to have the higher absorption wavelength?

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Which of the following best describes the following molecule?

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How many ð electron pairs are in the following molecule of benzamide?

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Which of the following is an accurate description of benzene?

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Amide bonds undergo free rotation at room temperature.

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The following molecule shown below is Lipitor,a drug prescribed to lower cholesterol levels.How many aromatic rings does it contain,how many ð electron pairs are part of its conjugated system,and how many atoms are part of its conjugated system?

Correct Answerverified4 aromatic...View AnswerShow Answer

Benzyne (shown below)is a highly reactive yet still aromatic derivative of benzene.It is planar and cyclic,but has eight ð electrons instead of six.Explain how it is still aromatic yet but still defies Hückel's rule.

Correct AnswerverifiedHückel's rule represents ð electrons in ...View AnswerShow Answer

Which of the following is NOT a criterion for aromaticity?

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Which of the following best describes double bonds in aromatic systems?

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Initially,both A and B are non-aromatic....
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4 aromatic...
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Hückel's rule represents ð electrons in ...
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