Benzene on treatment with a mixture of conc. $HNO_3$ and conc. $H_2SO_4$ at $90^\circ C$ gives :

Identify the correct statements for a ring system to exhibit aromaticity.
$(i)$ It must not be planar.
$(ii)$ It must possess $(4n+2) \pi$-electrons.
$(iii)$ It must be planar.
$(iv)$ It must possess $4n \pi$-electrons.
The correct answer is

The species responsible for nitration and sulphonation by nitric acid/conc. $H_2SO_4$ and fuming $H_2SO_4$ are :

Which of the following compounds is/are aromatic?

The nitration of benzene using nitric acid and sulfuric acid is an example of which of the following reactions?

What products are formed when the following compound is treated with $Br_2$ in the presence of $FeBr_3$?