Atoms can combine to achieve an octet of valence electrons by sharing electrons. Two fluorine atoms, for example, can form a stable F₂ molecule in which each atom has an octet of valence electrons by sharing a pair of electrons.

A pair of oxygen atoms can form an O₂ molecule in which each atom has a total of eight valence electrons by sharing two pairs of electrons.

The term covalent bond is used to describe the bonds in compounds that result from the sharing of one or more pairs of electrons.

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