Bonding Theories in Chemistry

1. VSEPR Theory - valence shell electron pair repulsion theory. Bonds are formed by sharing a pair of electrons.

2. Valence Bond Theory - Bonds are formed by overlapping atomic orbitals of one atom with atomic orbitals of a second atom.

3. Hybrid Orbital Theory - Bonds are formed by overlapping hybrid orbitals of one atom with atomic or hybrid orbitals of a second atom. The hybrid orbitals are formed by combining atomic orbitals within a single atom.

4. Molecular Orbital Theory - Bonds are formed due to electrons residing in molecular orbitals. Molecular orbitals are made by combining atomic orbitals of two or more different atoms into an orbital that is common to the whole molecule.