The carbon atom in co exhibits a lone pair. in what type of atomic orbital does this lone pair on c reside?

sp atomic orbital

Explanation:

CO has a triple bond, which is composed of one sigma bond and two pi bonds. Pi bonds are formed using one p orbital from each atom, so the carbon atom must have two unhybridized p orbitals in order to form two pi bonds. The other s and p orbitals that it has are hybridized together to form two sp orbitals. One of the sp orbitals is used in the sigma bond and the other holds the lone pair.

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