# Which of the following statement is not correct ?

(a) Double bond is shorter than a single bond.

(b) Sigma bond is weaker than a $\pi$ bond.

(c) Double bond is stronger than a single bond.

(d) Covalent bond is stronger than hydrogen bond

The statement which is not correct is sigma bond is weaker than a $\pi$ bond because sigma bond is generally stronger than a $\pi$ bond.
Hence b is the correct answer.