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    Tm

    Thulium

    Lanthanide

    Atomic Number: 69 • Atomic Mass: 168.9300 u • Period: 6 • Group: 101

    Electron Configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹³
    Phase: Solid
    Electronegativity: 1.25
    Erbium (Er)Ytterbium (Yb)
    OverviewPropertiesAtomic StructureOccurrenceApplicationsHistory

    History

    Thulium has been known since ancient times

    Historical Timeline

    Discovered in erbia (erbium oxide)

    Pure metal first produced in 1911