Chemistry - Aromatic Hydrocarbon Question with Solution | TestHub

Side chain hydrogen atoms are substituted by halogens in presence of light or heat by free radical mechanism. Ring hydrogens are substituted in presence of Lewis acid by electrofile. Alkyl halide (R-X) are reduced by Zn/HCl into alkane.

The degree of unsaturation for compound ${\mathrm{C}}_7{\mathrm{H}}_8$ is three $\left(3\right)$, as it reacts with ${\mathrm{Cl}}_2/\mathrm{\Delta }.$ Hence ${\mathrm{C}}_7{\mathrm{H}}_8$ is toluene, i.e ${\mathrm{C}}_6{\mathrm{H}}_5.{\mathrm{CH}}_3.$ The whole reaction occurs as follows: