Question

Is CO a strong bond?

Answer 1

Compounds with formal $C\equiv O$ triple bonds do not exist except for carbon monoxide, which consists of a very short, strong bond (112.8 pm). Such triple bonds possess a very high bond energy, even higher than $N\equiv N$ triple bonds.

Complete step by step answer: Most of the transition metals form homoleptic carbonyls. Some examples, having simple, well-defined structures.
The M-C sigma bond is formed by donation of a lone pair of electrons of carbonyl carbon into a vacant orbital of metal. The M-C pi bond is formed by donation of electron pairs from a filled d-orbital of metal into vacant antibonding orbital of CO.
Synergic Bonding: If a ligand donates electron pair to metal atom/ion and accepts electron pair from d-orbital of metal atom/ion, then it is called synergic bonding and ligands are called T-acid ligands, e.g CN, CO, NO.
In relation to $C=O$. Bond polarity is very normal due to the electronegative contrast between the oxygen and carbon atoms. This bond is also an ionic bond, while the carbon carbon bond is a covalent bond with no difference in electronegativity. As a consequence, $C=O$ is a better bond than $C=C$.
The carbon monoxide molecule is accurately represented by a triple covalent bond between the carbon and oxygen atoms. - of the bonds is a coordinate covalent bond, which means that one of the atoms contributes all of the electrons in the reciprocal pair.

Note: Bond length of compounds is inversely proportional to the bond order of the compound. The metal to ligand bonding produces a synergic effect which strengthens the bond between CO and the metal. The compounds containing synergic bonds are exceptionally stable.