Q. Which one of these is not true for benzene?
A) It forms only one type of monosubstituted product.
B) There are three carbon-carbon single bonds and three carbon-carbon double bonds
C) The heat of hydrogenation of benzene is less than the theoretical value.
D) The bond angle between the carbon-carbon bonds is $120{^\circ}$.
Explanation
(b)
The structure of benzene is
[image:13_image253.emf]
$Bond\ order = \frac{number\ of\ bonds}{number\ of\ resonating\ structures}$
$= \frac{4}{3} = 1.33$
Since, the bond order is in between single and double bond, thus, it contains delocalised $\pi$-bonds. Hence, it is not possible to obtain number of single and double bonds in benzene.
[image:13_image254.emf]
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.