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    IsotopeAtomic mass (Da)Isotopic abundance (amount fraction)
    19F18.998 403 162(5)1

    Fluorine is a monoisotopic element and its atomic weight is determined solely by its isotope 19F. The Commission last revised the standard atomic weight of fluorine in 2021 based on the latest Atomic Mass Evaluation by IUPAP.

    SOURCE  Atomic weights of the elements: Review 2000 by John R de Laeter et al. Pure Appl. Chem. 2003 (75) 683-800
    © IUPAC 2003


    Ar(F) = 18.998 403 162(5) since 2021

    The name derives from the Latin fluere for "flow" or "flux" because fluorite (CaF2) was used as a flux in metallurgy owing to its low melting point. It was discovered in hydrofluoric acid by the Swedish pharmacist and chemist Carl-Wilhelm Scheele in 1771, but it was not isolated until 1886 by the French pharmacist and chemist Henri Moissan.