Question

What is the bond length of C = C in benzene?
(A) 139 pm
(B) 133 pm
(C) 154 pm
(D) 111 pm

Answer 1

Answer:

Option B is correct

133pm is the bond length

Answer 2

The bond length of C = C double bond in benzene is (A) 139 pm.

Benzene is a cyclic aromatic compound, with a six-membered carbon atom, and six hydrogen atoms. There are alternating single and double bonds in the pictorial representation. However, due to electron delocalisation, we obtain partial double bonds with bond length shorter than a C - C single bond (154 pm), but longer than a C = C double bond (134 pm). This delocalisation gives rise to a pi-electron cloud both above and below the benzene plane.