Atoms have a tendency to complete their outer energy level. this is known as

decomposition
synthesis
the octet rule
the rule of electrons

the octet rule

Explanation:

    The Octet Rule states that the atoms of the elements bond together in an attempt to complete their valence layer (last layer of the electrosphere). The name “octet rule” arose from the established amount of electrons for the stability of an element, ie the atom is stable when it has 8 electrons in its valence layer.

    To achieve such stability as suggested by the Octet Rule, each element must gain or lose (share) electrons in the chemical bonds, so they acquire eight electrons in the valence shell.

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