Do we always assume hybridization is necessary when a compound is formed from two atomic orbitals of differing energy levels? such as a molecule having 2 electrons in 2s and 2 electrons in the 2p orbital? (If orbitals of different energy are contributing to the formation of a chemical bond, and we are interested in the energy of electrons of the bond, we need to look at the relative contribution of those orbitals, and that is what hybridization is. It is not a real process, it is a theoretical tool. - GS). Thanks!