Question

Among the given species the one which contains weakest carbon- oxygen bond : $\text{CO}_{\text{2}} \text{,} \, \text{CH}_{\text{3}} \text{COO}^{-} \text{,} \, \text{CO,} \, \text{CO}_{\text{3}}^{\text{2} -}$

• A. $CO_{2}$
• B. $CH_{3}COO^{-}$
• C. $CO$
• D. $CO_{3}^{ 2 -}$

Answer 1

Answer: (D)

$\text{Bond} \, \text{strength} \, \propto \, \text{Bond} \, \text{order}$

Bond order is determined through resonating structure. Among the given species, the bond dissociation energy of $C-O$ bond is minimum in case of $CO_{3}^{2 -}$ by which $C-O$ bond become more weaker in $CO_{3}^{2 -}$ or the bond order of $CO_{3}^{2 -}$ (1.33) is minimum so the bond become weaker.