Toluene is oxidised to benzoic acid by

In which of the following compounds does electrophilic aromatic substitution take place in the phenyl ring present on the left-hand side?

Which of the following compounds would not be considered aromatic in its behaviour?

Give reason: Nitration of benzene is not possible with only $HNO_3$.

Friedel-Crafts acylation reaction can be used to obtain the compounds:

The reaction of benzene with a mixture of concentrated $HNO_3$ and concentrated $H_2SO_4$,followed by treatment with $Cl_2 / FeCl_3$,gives: