Question

Which one of the following statements is not correct for sigma- and pi- bonds formed between two carbon atoms? 

(a) Sigma-bond is stronger than a pi-bond. 

(b) Bond energies of sigma- and pi-bonds are of the order of 264 kJ/mol and 347 kJ/mol, respectively. 

(c) Free rotation of atoms about a sigma-bond is allowed but not in case of a pi-bond. 

(d) Sigma-bond determines the direction between carbon atoms but a pi-bond has no primary effect in this regard.

Answer 1

The correct option is : (b) Bond energies of sigma- and pi-bonds are of the order of 264 kJ/mol and 347 kJ/mol, respectively. 

Explanation:

We know C - C = 347 kJ/mol

C = C = 619 kJ/mol