Question

The correct order of increasing $C-O$ bond length of $CO, C{O}_3^{2-}, C{O}_2$ is:

• (A) $C{O}_3^{2-}<C{O}_{2 }<CO$
• (B) $C{O}_2 < C{O}_3^{2-} < CO$
• (C) $CO < C{O}_3^{2-} <C{O}_2$
• (D) $CO < C{O}_{2}M < C{O}_3^{2-}$

Answer 1

The Correct Option is C

Explanation:
The order of $C-O$ bond length in the given species can be determined by finding out the number of bonds between the constituent atoms.The structures of the given species are as follows:1. $CO:{}^{-}C\equiv O^{+}$There is a triple bond between $C$ and $O$ atoms.2. $C{O}_2:O\equiv C=O$There are two double bonds between $C$ and $O$atoms.3. $C{O}_3^{2-}$

There is a single, as well as a double-bond, showed between $C$ and $O$atoms.From the above structures, it is clear that bond order for the given compounds increases as:$C{O}_3^{2-}<C{O}_2<CO$We know that Bond Length ∝$\frac{1}{bondorder}$Thus, the increasing order of $C-O$ bond length is:$CO<C{O}_{2}M<C{O}_3^{2-}$Hence, the correct option is (D).

Answer 2

Ans: The bond length of C-O in the following compounds are: 

 

The bond length is shorter in CO₂ as compared to CO₃²⁻  . This is because the oxygen forms a double bond with a carbon atom and, double bond is shorter than the single bond. The bond order of carbon dioxide is 2. 

CO₃²⁻ has a longer C-O bond that carbon dioxide. It forms a single bond with Oxygen.  The bond order for CO₃²⁻ is 1.33. 

CO forms a triple bond. The bond order of CO is 3. 

• The bond length is triple bond< double bond< single bond 
• And as Bond length is inversely proportional to bond order. 

Therefore, CO< CO₂ < CO₃²⁻