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[L. molecula, little mass]
ABBR: mol Any electrically neutral aggregate of atoms held together strongly enough to be considered as a unit. The individual atoms in the molecule may be of the same type or different. Combinations of dissimilar atoms form chemical compounds. The positive and negative electrical charges balance exactly. Excess or deficiency of either positive or negative charge by the loss or acquisition of electrons results in the formation of an ion.
A molecule is designated by the number of atoms it contains, as monatomic (one atom); diatomic (two); triatomic (three); tetratomic (four); pentatomic (five); or hexatomic (six).

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