Discuss the formation of cancer-causing polynuclear hydrocarbons and explain how they cause cancer.

Which of the following is a Friedel-Crafts reaction $(FCR)$?

Select the true statement about benzene from amongst the following.

Which one of the following compounds is not aromatic?

The order of decreasing reactivity towards an electrophilic reagent,for the following compounds,is:
$(i) \text{ Benzene} \quad (ii) \text{ Toluene} \quad (iii) \text{ Chlorobenzene} \quad (iv) \text{ Phenol}$

The reaction$(s)$ leading to the formation of $1,3,5-$trimethylbenzene is (are):
$(A)$ $3CH_3COCH_3 \xrightarrow{Conc. H_2SO_4, \Delta} 1,3,5-\text{trimethylbenzene}$
$(B)$ $3CH_3C \equiv CH \xrightarrow{\text{heated iron tube}, 873 K} 1,3,5-\text{trimethylbenzene}$
$(C)$ $1,3,5-\text{triacetylbenzene} \xrightarrow{1) Br_2, NaOH, 2) H_3O^+, 3) \text{sodalime}, \Delta} \text{benzene}$
$(D)$ $1,3,5-\text{triformylbenzene} \xrightarrow{Zn/Hg, HCl} 1,3,5-\text{trimethylbenzene}$