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    Cs

    Cesium

    Alkali Metal

    Atomic Number: 55 • Atomic Mass: 132.9100 u • Period: 6 • Group: 1

    Electron Configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s¹
    Phase: Solid
    Electronegativity: 0.79
    Xenon (Xe)Barium (Ba)
    OverviewPropertiesAtomic StructureOccurrenceApplicationsHistory

    History

    Cesium has been known since ancient times

    Historical Timeline

    Discovered through spectroscopic analysis

    First element discovered using spectroscopy