Covalent bonds involve the overlap of what?

• A. Electron shells
• B. Ions
• C. Delocalized electrons
• D. Lattice energy

Answer: (A)

Covalent bonds form when atoms share electrons by overlapping their electron clouds (orbitals) in the outer regions of their atoms. This overlap creates a shared region of high electron density that both nuclei feel, pulling the atoms together and holding them as a molecule. The overlap occurs in the electron shells, where the orbitals reside, allowing the shared electrons to be attracted to both nuclei at once. If electrons were merely transferred, you'd get ions and an ionic bond; delocalized electrons describe other bonding situations (like metals or some carbon structures), and lattice energy relates to the energy in an ionic crystal, not a simple covalent bond.