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    No

    Nobelium

    Actinide

    Atomic Number: 102 • Atomic Mass: 259.0000 u • Period: 7 • Group: 102

    Electron Configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁶ 7s² 5f¹⁴
    Phase: Solid
    Electronegativity: 1.3
    Mendelevium (Md)Lawrencium (Lr)
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    Physical & Chemical Properties

    Physical Properties

    • •Presumed to be metallic
    • •Highly radioactive
    • •Properties mostly theoretical
    Melting Point

    1100 K (826.85 °C, 1520.33 °F)

    Boiling Point

    2013 K (1739.85 °C, 3163.73 °F)

    Density

    9.9 g/cm³

    Electronegativity

    1.3 (Pauling scale)

    Chemical Properties

    • •Forms predominantly +2 oxidation state
    • •Similar to ytterbium chemically
    • •No(II) is more stable than No(III)

    Electron Configuration

    1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁶ 7s² 5f¹⁴

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