MCQ Multiple Choice Question on Polycyclic Aromatic Hydrocarbon

Polycyclic Aromatic Hydrocarbon

1.  Which is the most probable main product of the following reaction ?

   

 Answer:- b.

Electrophilic substitution on naphthalene occurs preferentially at C1/ α carbon.

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2. Which is the most probable main product of the following electrophilic substitution reaction of napphthalene?

Answer:-a. 

The most reactive site of naphthalene is C1 and remember that amino NH2 group is an activating, o,p-directing group in aromatic electrophilic substitution reaction; consequently, nitration occurs predominantly at C4 in this reaction.

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3. Which is the most probable main product of the following reaction?

Answer:- d.

Electrophilic substitution on anthracene occurs preferentially at C 9 carbon.
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4.  Which is impossible as a resonance contributor of anthracene.

 

Answer:- b.

In this structure two carbon atoms with five valencies.

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5. Which of following is the most important resonance contributing structure of the naphthalenium ion intermediate in an electrophilic substitution reaction of naphthalene?

 

Answer:- a.

In this one of the benzene ring having benzenoid i.e sexted state, rest of structure not.

Thank you.