Aromatic Compounds and Electrophilic Substitution - Applications
Q. In the nitration of benzene, which reagent is used to generate the nitronium ion?
A.HNO3
B.H2SO4
C.HCl
D.NaNO2
Solution
In the nitration of benzene, concentrated sulfuric acid (H2SO4) is used to generate the nitronium ion (NO2+) from nitric acid (HNO3).
Correct Answer: B — H2SO4
Q. What is the effect of a nitro group on the reactivity of a benzene ring in electrophilic substitution?
A.Activates the ring
B.Deactivates the ring
C.No effect
D.Makes the ring non-reactive
Solution
A nitro group is a strong electron-withdrawing group that deactivates the benzene ring, making it less reactive towards electrophilic substitution.
Correct Answer: B — Deactivates the ring
Q. What is the IUPAC name of the compound with the formula C6H5NO2?
A.Nitrobenzene
B.Aniline
C.Benzamide
D.Benzonitrile
Solution
The IUPAC name of C6H5NO2 is nitrobenzene, which contains a nitro group (-NO2) attached to a benzene ring.
Correct Answer: A — Nitrobenzene
Q. What is the product of the Friedel-Crafts acylation of benzene with acetyl chloride?
A.Acetophenone
B.Benzophenone
C.Benzyl acetate
D.Phenyl acetate
Solution
The product of the Friedel-Crafts acylation of benzene with acetyl chloride is acetophenone, where an acyl group is introduced to the benzene ring.
Correct Answer: A — Acetophenone
Q. What is the role of a catalyst in electrophilic aromatic substitution reactions?
A.To stabilize the product
B.To generate the electrophile
C.To increase the temperature
D.To decrease the reaction time
Solution
The catalyst in electrophilic aromatic substitution reactions, such as AlCl3 or FeBr3, is used to generate the electrophile that will react with the aromatic compound.
Correct Answer: B — To generate the electrophile
Q. Which of the following compounds undergoes electrophilic substitution most readily?
A.Toluene
B.Benzene
C.Nitrobenzene
D.Chlorobenzene
Solution
Toluene undergoes electrophilic substitution most readily due to the electron-donating effect of the methyl group, which activates the benzene ring.
Correct Answer: A — Toluene
Q. Which of the following reactions is an example of electrophilic aromatic substitution?
A.Hydrogenation of benzene
B.Nitration of benzene
C.Oxidation of toluene
D.Reduction of nitrobenzene
Solution
Nitration of benzene is an example of electrophilic aromatic substitution, where a nitro group replaces a hydrogen atom on the benzene ring.
