Chapter 14, Problem 93CP

Carbon monoxide $\text{(CO)}$ forms bonds to a variety of metals and metal ions. Its ability to bond to iron in hemoglobin is the reason that $\text{CO}$ is so toxic. The bond carbon monoxide forms to metals is through the carbon atom:

1. On the basis of electronegativities, would you expectthe carbon atom or the oxygen atom to form bondsto metals?
2. Assign formal charges to the atoms in $\text{CO}$ . Whichatom would you expect to bond to a metal on thisbasis?
3. In the $\text{MO}$ model, bonding $\text{MOs}$ place more electrondensity near the more electronegative atom. (See the $\text{HF}$ molecule, $\text{Figs}\text{. 14}\text{.45}$ and $\text{14}\text{.46}$ .) Antibonding $\text{MOs}$ place more electron density near the less electronegative atom in the diatomic molecule. Use the $\text{MO}$ model to predict which atom of carbon monoxide should form bonds to metals.