Dear vijay,
It consists of one carbon atom and one oxygen atom, connected by a covalent double bond and a dative covalent bond. It is the simplest oxocarbon, and is an anhydride of formic acid. In coordination complexes the carbon monoxide ligand is called carbonyl.
The bond length of CO is consistent with a partial triple bond, and the molecule can be represented by three resonance structures

-
We are all IITians and here to help you in your IIT JEE preparation.
All the best.
If you like this answer please approve it....
win exciting gifts by answering the questions on Discussion Forum
Sagar Singh
B.Tech IIT Delhi