The heat of hydrogenation of one double bond in cyclohexene is $28.6 \, kcal \, mol^{-1}$ and the heat of hydrogenation of benzene to cyclohexane is $50 \, kcal \, mol^{-1}$. The resonance stabilization energy of benzene is ...... $kcal \, mol^{-1}$.

What type of difference is observed in the hybridization of carbon in benzene during nitration and the formation of the $\sigma$-complex?

Which of the following statements are correct?
$I$. In nitrating mixture,nitric acid participates as an acid.
$II$. $\sigma$-complex is the intermediate substance in electrophilic substitution of benzene.
$III$. Benzene on Friedel-Crafts alkylation with $n$-propyl chloride gives isopropyl benzene.

The reaction of benzene with $CO$ and $HCl$ in the presence of anhydrous $AlCl_3$ gives :

Which of the following is true about the following groups when attached to a benzene ring?

Answer the following questions: Write in brief about the reaction steps of the sulphonation reaction of benzene and its mechanism.