((number of electrons in bonding orbitals)-(number of electrongs in antibonding orbitals))/2
unbonded electron
When all electron pairs are filled
s are all sigma, p and d all start with a sigma the rest are pi
sp
sp2
sp3
sp3d
sp3d2
(number of atoms bonded to central atom) + (number of lone pairs on central atom)
Linear
Trigonal Planar, Bent
Tetrahedral, Trigonal Pyramidal, Bent
Trigonal Bipyramidal, See-saw, T-shape, Linear
Octahedral, Square Pyramidal, Square Planar
Steric Number 2
Steric Number 3
Steric Number 4
Steric Number 5
Steric Number 6
Linear
Trigonal Planar
Trigonal Bipyramidal
Octahedral
(Valence e-) - (Number of unbonded e-) - (1/2 bonded e-)