Question

The correct order of $Cl-O$ bond lengths in $\text{ClO}^{-} , \text{ClO}_{2}^{-} , \text{ ClO}_{3}^{-} , \text{ClO}_{4}^{-}$ is

• A. $\text{ClO}^{-} < \text{ClO}_{2}^{-} < \text{ClO}_{3}^{-} < \text{ClO}_{4}^{-}$
• B. $\text{ClO}_{4}^{-} < \text{ClO}_{3}^{-} < \text{ClO}_{2}^{-} < \text{ClO}^{-}$
• C. $\text{ClO}_{3}^{-} < \text{ClO}_{4}^{-} < \text{ClO}_{2}^{-} < \text{ClO}^{-}$
• D. $\text{ClO}_{4}^{-} = \text{ClO}_{3}^{-} < \text{ClO}_{2}^{-} < \text{ClO}^{-}$

Answer 1

Answer: (B)

Bond length is inversely proportional to bond order. Greater the delocalization of $\pi e^{-}\left(\right.-ve \, \, charge\left.\right)$ shorter the bond length.