Question

Increasing order of carbon-oxygen bond length in $CO,C{O}_2$ and $C{O}_3{}^{2-}$ is

• A. $CO<C{O}_2<C{O}_3{}^{2-}$
• B. $CO<C{O}_3{}^{2-}<C{O}_2$
• C. $C{O}_3{}^{2-}<C{O}_2<CO$
• D. $C{O}_3{}^{2-}<C{O}_2=CO$

Answer 1

Answer: (A)

Bond order of carbon-oxygen
in $CO$ is $3$
in $C{O}_2$ is $2$
in $C{O}_3^{2-}$ is $1.33$ (Due to resonance)
Bond order $\propto \frac{1}{E}$
Bond length
Structure

resonance stabilised