Question

Select the statements below that are TRUE.

A: Benzene and its derivatives tend to undergo electrophilic aromatic addition reactions.

B: Benzene and its derivatives tend to undergo electrophilic aromatic substitution reactions.

C: Substitution reactions have energies of activation that are very low.

D: Dienes and alkenes are much more stable than benzene rings.

E: Addition reactions destroy the integrity of the benzene ring.

F: Benzene and its derivatives undergo a type of substitution reaction in which a hydrogen atom is replaced by a substituent, but the stable aromatic benzene ring is regenerated at the end of the mechanism.

HINT: There are 3 correct answers

Answer 1

Concepts and reason

This problem is based on the concept of reactions of benzene and its derivatives.

Benzene and its derivatives usually undergo electrophilic substitution reactions. In electrophilic substitution reactions benzene ring attacks on the electrophilic species in order to make a substituted product.

Fundamentals

Benzene works as a nucleophile in electrophilic substitution reaction because of its high electron density due to the presence of electron cloud of six pi-electrons.

(A)

Benzene and its derivatives undergo substitution reactions with electrophiles which involve the replacement of hydrogen atom. They do not show electrophilic aromatic addition reactions.

(B)

Benzene and its derivatives undergo substitution reactions with electrophiles which involve the replacement of hydrogen atom. They do not show electrophilic aromatic addition reactions.

(C)

The activation energy in case of substitution energy is very high. Because the activated complex in case of aromatic compounds has very high energy.

(D)

Benzene ring has electron delocalization of 6 pi-electrons which makes them much more stable the dienes and alkenes.

(E)

Addition reactions involve the addition of an electrophile to the double bond which will actually break the continuous delocalization of benzene ring.

(F)

An electrophilic substitution reactions of benzene ring involve the replacement of hydrogen atom with the electrophilic in order to give the substituted product and benzene is regenerated in the final stage of electrophilic substitution reactions.

Ans: Part A

Benzene and its derivatives tend to undergo electrophilic aromatic addition reactions is a false statement.