Hydrogen bonds are usually longer than covalent bonds. Give an example where covalent and hydrogen bonds are equal in length. Explain.

Explanation

In bifluride ion `(HF_(2)^(-))`, the covalent bond annd the hydrogen bond are equal in lengvth and this is due to the fact that the structure of this ion is a resonance hybrid of structures I and II.
`[underset((I))(F-H-F^(Theta))harr underset((II))(F^(Theta)-H-F)]`