Previous Year NEET Question- Chemical Bonds L-9

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 $264 \mathrm{~kJ} / \mathrm{mol}$ and $347 \mathrm{~kJ} / \mathrm{mol}$, 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: Bond energies of sigma- and pi-bonds are of the order of $264 \mathrm{~kJ} / \mathrm{mol}$ and $347 \mathrm{~kJ} / \mathrm{mol}$, respectively.#

Solution:#

Sigma bond dissociation energy = 347 kJ/mol Pi-bond dissociation energy = 264 kJ/mol