Which of the following statements are correct with respect to benzene? (i) It forms triozonide with $\mathrm{O}_3$. (ii) It is non-planar. (iii) It forms only one monosubstituted product with $\mathrm{CH}_3 \mathrm{COCl}$ in the presence of anhyd. $\mathrm{AlCl}_3$. (iv) If forms hexachlorobenzene on heating with $\mathrm{Cl}_2$ under photochemical condition.

• A

  (i), (ii)
• B

  (ii), (iii)
• Correct answer
  C

  (i), (iii)
• D

  (iii), (iv)

Solution

(ii) Benzene is a planar molecule. (iii) Benzene when treated with a mixture of ethanoyl chloride $\mathrm{CH}_3 \mathrm{COCl}$ and aluminium chloride as catalyst. A ketone called phenyle thanone (monosubstituted) is obtained.
(iv) Benzene when heated with $\mathrm{Cl}_2$ under photochemical condition gives $1,2,3,4,5,6$-hexachlorocyclohexane.

Hence, the correct answer is option: 'C'.