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    Np

    Neptunium

    Actinide

    Atomic Number: 93 • Atomic Mass: 237.0000 u • Period: 7 • Group: 102

    Electron Configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁶ 7s² 5f⁴ 6d¹
    Phase: Solid
    Electronegativity: 1.36
    Uranium (U)Plutonium (Pu)
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    Physical & Chemical Properties

    Physical Properties

    • •Silvery appearance
    • •Highly radioactive metal
    • •Ductile when pure
    Melting Point

    917 K (643.85 °C, 1190.93 °F)

    Boiling Point

    4273 K (3999.85 °C, 7231.73 °F)

    Density

    20.45 g/cm³

    Electronegativity

    1.36 (Pauling scale)

    Chemical Properties

    • •Multiple oxidation states (+3 to +7)
    • •Forms colored compounds
    • •Reacts with oxygen and acids

    Electron Configuration

    1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁶ 7s² 5f⁴ 6d¹

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