question_answer

Which gives only mono-substituted product?

A)  o-dinitrobenzene

B)  m-dinitrobenzene

C)  p-dinitrobenzene

D)  Nitrobenzene

Correct Answer: B

Solution :

Nitro group is meta directing group.            From the above structures it is clear that only one meta position is possible in m-dinitrobenzene and other choices have more than one meta positions. \[\therefore \] m-dinitrobenzene [b] is the correct answer.