The three most stable oxides of carbon are carbon monoxide (CO), carbon dioxide \(\left(\mathrm{CO}_{2}\right)\), and carbon suboxide \(\left(\mathrm{C}_{3} \mathrm{O}_{2}\right)\). The space-filling models for these three compounds are For each oxide, draw the Lewis structure, predict the molecular structure, and describe the bonding (in terms of the hybrid orbitals for the carbon atoms).

First, let's determine the number of valence electrons for each element: - Carbon (C) has 4 valence electrons - Oxygen (O) has 6 valence electrons For CO, there is one carbon and one oxygen atom, so we have 4 + 6 = 10 valence electrons. For CO₂, there is one carbon and two oxygen atoms, so we have 4 + 2(6) = 16 valence electrons. For C₃O₂, there are three carbon and two oxygen atoms, so we have 3(4) + 2(6) = 22 valence electrons. Now we can draw the Lewis structures for each oxide: - CO: O triple bond C - CO₂: O double bond C double bond O - C₃O₂: C=C=C(O)₂.

Next, we'll predict the molecular structure based on the Lewis structures by determining the electron domain geometry and molecular geometry. For CO, carbon has 3 electron domains (3 bonding pairs). The electron domain geometry is trigonal planar, giving a linear molecular geometry with a bond angle of 180°. For CO₂, carbon has 2 electron domains (2 bonding pairs). The electron domain geometry is linear, giving a linear molecular geometry with a bond angle of 180°. For C₃O₂, the carbon atoms on the ends, C1 and C3, both have 3 electron domains (2 bonding pairs and 1 lone pair). Their electron domain geometries are trigonal planar, giving a bent molecular geometry with a bond angle of less than 120°. The middle carbon, C2, has 2 electron domains (2 bonding pairs). Its electron domain geometry is linear, giving a linear molecular geometry with a bond angle of 180°.

Now we'll describe the bonding in terms of hybrid orbitals for the carbon atoms in each oxide. For CO, carbon uses sp hybrid orbitals to form 2 sigma bonds with oxygen, and one pi bond. This results in a triple bond between carbon and oxygen – one sigma bond and two pi bonds. For CO₂, carbon is sp hybridized, forming two sigma bonds with the oxygen atoms in the double bonds. The pi bonds consist of one remaining p orbital in the carbon atom overlapping with a p orbital in each oxygen atom. For C₃O₂, C1 and C3 carbon atoms are both sp² hybridized, with each forming two sigma bonds and one lone pair. The bond between C1 and C3 is a double bond, with one sigma bond and one pi bondf. The bonds between C1 and C2, and C3 and C2, are sigma bonds. C2 carbon atom is sp hybridized, forming two sigma bonds.