Benzene has the following structural formula.

(b) Which statement best describes the carbon–carbon bonds in benzene? (i) Three carbon–carbon bonds are longer and weaker than the other three carbon–carbon bonds. (ii) All six carbon–carbon bonds are identical, and their length and strength are between a double and single bond. (iii) The length of carbon–carbon double bond switches back and forth between the length of a double and a single bond.