What is the molecular geometry of CO?

The molecular geometry of carbon monoxide (CO) is linear due to the arrangement of its atoms and the electron pairs around the carbon and oxygen nuclei. CO consists of a carbon atom triple-bonded to an oxygen atom, which means there are no lone pairs on the carbon atom that would otherwise cause a deviation from linearity.

In molecular geometry, a linear shape occurs when there are two atoms bonded to a central atom with no lone pairs influencing the geometry, creating a straight line with a bond angle of 180 degrees. For CO, the presence of the triple bond—consisting of one sigma bond and two pi bonds—between carbon and oxygen reinforces this linear structure.

Alternatively, if the molecular geometry were T-shaped, bent, or trigonal pyramidal, factors such as lone pairs or additional bonded atoms would need to be present, which is not the case for CO. Thus, the simple two-atom framework results in a linear molecular geometry.