Mo

    Molybdenum

    Transition Metal

    Atomic Number: 42 • Atomic Mass: 95.9500 u • Period: 5 • Group: 6

    Electron Configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s¹ 4d⁵
    Phase: Solid
    Electronegativity: 2.16

    Physical & Chemical Properties

    Physical Properties

    • Silvery-gray metal with high melting point (2896 K or 2623°C)
    • One of the most refractory metals
    • High thermal conductivity
    • Low thermal expansion coefficient
    • High elastic modulus (stiffness)
    Melting Point

    2896 K (2622.85 °C, 4753.13 °F)

    Boiling Point

    4912 K (4638.85 °C, 8381.93 °F)

    Density

    10.22 g/cm³

    Electronegativity

    2.16 (Pauling scale)

    Chemical Properties

    • Forms passivation layer of molybdenum trioxide in air
    • Multiple oxidation states from -2 to +6, with +4 and +6 being most common
    • Resistant to corrosion and most chemical attacks
    • Does not react with oxygen at room temperature
    • Forms many organometallic compounds

    Electron Configuration

    1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s¹ 4d⁵

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