What is a covalent bond?

A covalent bond occurs between two non metals. It involves two atoms sharing electrons. The electrostatic attraction is between the positive nuclei and the negative charge on the shared pair of electrons. Atoms that are covalently bonded are called molecules (usually called simple molecular structures). Covalent bonds do not conduct electricity in any state because they do not contain mobile charged particles, they have low melting and boiling points because of the weak intermolecular forces that hold covalent molecules together.