Final answer:
An sp hybridized carbon atom has two valence electrons in sp orbitals and two in p orbitals, forming a triple bond with linear geometry as seen in acetylene.
Step-by-step explanation:
A carbon atom that is sp hybridized will have two valence electrons occupying sp orbitals and two valence electrons occupying p orbitals. This hybridization occurs when a carbon atom is involved in the formation of a triple bond or two double bonds, resulting in a linear geometry, as in the case of acetylene (H-C=C-H). In this scenario, two sp hybrid orbitals form a σ (sigma) bond between the carbon atoms and with the hydrogen atoms. The two unhybridized p orbitals on each carbon atom overlap side by side to form two π (pi) bonds, accounting for a triple bond between the two carbon atoms.