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 $\pi e^{-}(-vecharge)$ shorter the bond length.