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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)
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    Physical & Chemical Properties

    Physical Properties

    • •Soft silvery-gold metal
    • •Low melting point
    • •Highly reactive
    Melting Point

    301.59 K (28.44 °C, 83.19 °F)

    Boiling Point

    944 K (670.85 °C, 1239.53 °F)

    Density

    1.873 g/cm³

    Electronegativity

    0.79 (Pauling scale)

    Chemical Properties

    • •Violently reactive with water
    • •Oxidizes rapidly in air
    • •Forms ionic compounds

    Electron Configuration

    1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s¹

    Electron configuration describes how electrons are distributed in atomic orbitals, showing how they are arranged in energy levels and subshells.