Question

Among the following which one will have the largest $O-O$ bond length?

• A. $K{O}_2$
• B. $O_2$
• C. $O_2^{+}{\left[As{F}_6\right]}^{-}$
• D. $K_2{O}_2$

Answer 1

Answer: (D)

$K_2{O}_2$

The bond orders of $O_2^{-}$, $O_2$, $O_2^{+}$ and $O_2^{2-}$ ions present in $K{O}_2$, $O_2$, $O_2^{+}[As{F}_6{]}^{-}$ and $K_2{O}_2$ are $1.5,2,2.5$ and $1$ respectively. Thus, the bond order is lowest in $K_2{O}_2$. Hence, the $O-O$ bond length is maximum in $K_2{O}_2$.