Give the reaction for the acylation of benzene and its mechanism.

(N/A) The substitution of a hydrogen atom in the benzene ring with an acyl group $(-COR)$ is known as the acylation of benzene. These reactions are known as Friedel-Crafts acylation. For example,the formation of acetophenone from benzene is shown below:
$C_6H_6 + CH_3COCl \xrightarrow{Anhydrous \ AlCl_3, \Delta, \ 353K} C_6H_5COCH_3 + HCl$
$C_6H_6 + (CH_3CO)_2O \xrightarrow{Anhydrous \ AlCl_3} C_6H_5COCH_3 + CH_3COOH$
This reaction proceeds in three steps:
$(i)$ Formation of the electrophile $CH_3CO^+$:
$CH_3-CO-Cl + AlCl_3 \rightarrow CH_3-C^+O + AlCl_4^-$
$(ii)$ The electrophile $CH_3CO^+$ attacks the benzene ring to form a carbocation intermediate (arenium ion).
$(iii)$ Loss of a proton from the carbocation intermediate restores the aromaticity of the ring to form acetophenone.