Hybridization
- Mathematical model that describes the pattern of bonds found in a molecule (geometry)
- Explains difference between the electron configuration of a free atom and the electron configuration when an atom is part of a molecule
Hybrid orbitals
- Combine orbitals within the same atom
- Equal the number of atoms and lone pairs bound to the atom (the steric number)
- Average the properties (shape and arrangement) of their component atomic orbitals
- Are degenerate (equivalent)
- Position themselves as far apart as possible
sp2 Orbital
Now, let's see how hybrid orbitals position themselves as far apart as possible.
- Redraw the 2s atomic orbital of carbon.
- Then, draw 2px, 2py, and 2pz orbitals of carbon.
- Using two representative lobes, show that these lobes have a 90 degree separation: we randomly selected the y-z planes, here, any two planes would do.
- Then, draw 3 sp2 hybrid orbitals and give them maximum separation: 120 degree angles in the x-y plane.
- Being degenerate, hybrid orbitals position themselves as far apart as possible: they repulse each other for maximal spatial separation, in this instance, the orbitals point to the corners of a planar triangle.
- Finally, redraw the Lewis structure for ethylene.
- Indicate that the H-C-H and the H-C-C bond angles are 120 degrees.
- Thus, through hybridization we can account for the placement of electrons and predict molecular structures.