What does valence bond theory explain regarding chemical bonding?

Valence bond theory primarily focuses on the concept of atomic orbitals overlapping to form chemical bonds between atoms. This theory posits that when two atoms approach each other, the atomic orbitals of each atom can overlap, allowing for the pairing of their unpaired electrons. This overlap leads to the formation of a chemical bond, which can be characterized as either a sigma bond (formed by head-on overlap) or a pi bond (formed by side-on overlap).

The theory effectively explains the directional properties of bonds and how the specific shapes of molecules arise from the geometric arrangement of these overlapping orbitals. By considering the shapes and orientations of atomic orbitals, valence bond theory provides a solid framework for understanding how atoms bond together in molecular structures.

Other options, while they may be related to concepts of chemical bonding, do not encapsulate the primary focus of valence bond theory. For instance, although electron sharing is a result of overlapping orbitals in covalent bonds, it does not describe the mechanism of the overlap itself. Ionic bonds, on the other hand, involve the transfer of electrons rather than sharing, and electronegativity differences pertain more to the nature of bonds (polar vs. nonpolar) rather than the actual bonding mechanism described by