Carbon uses sp3, sp2, and sp hybridization when it forms compounds.
sp3 Hybridization
When a carbon atom bonds to four other atoms, it mixes one 2s and three 2p orbitals to form four new energetically equivalent sp3 hybrid orbitals.
These orbitals are at angles of 109.5 ° to each other and point toward the corners of a tetrahedron.
sp2 Hybridization
When a carbon atom bonds to three other atoms, it mixes one 2s and two of the three 2p orbitals to form three new energetically equivalent sp2 hybrid orbitals.
The sp2 orbitals are at angles of 120 ° to each other and point toward the corners of an equilateral triangle.
We say that they have a trigonal planar geometry.
The unhybridized 2p orbital is perpendicular to the plane of the sp2 orbitals.
sp Hybridization
When a carbon atom bonds to two other atoms, it mixes one 2s and one of the three 2p orbitals to form two new energetically equivalent sp hybrid orbitals.
The sp orbitals are at angles of 180 ° to each other and point directly away from each other in a straight line.
We say that they have a linear geometry.
The two unhybridized 2p orbitals are perpendicular to each other and to the sp orbitals.
![sp orbitals]()
The unhybridized p orbitals are used to make the π bonds in alkynes like ethyne.
![Ethyne]()
