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    O

    Oxygen

    Nonmetal

    Atomic Number: 8 • Atomic Mass: 15.9990 u • Period: 2 • Group: 16

    Electron Configuration: 1s² 2s² 2p⁴
    Phase: Gas
    Electronegativity: 3.44
    Nitrogen (N)Fluorine (F)
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    Physical & Chemical Properties

    Physical Properties

    • •Colorless, odorless, tasteless gas at standard conditions
    • •Pale blue as liquid and solid
    • •Slightly heavier than air
    • •Moderately soluble in water
    Melting Point

    54.36 K (-218.79 °C, -361.82 °F)

    Boiling Point

    90.2 K (-182.95 °C, -297.31 °F)

    Density

    0.001429 g/cm³

    Electronegativity

    3.44 (Pauling scale)

    Chemical Properties

    • •Highly reactive and forms oxides with most elements
    • •Supports combustion
    • •Forms hydrogen bonds in water
    • •Exists as diatomic O₂ in standard conditions

    Electron Configuration

    1s² 2s² 2p⁴

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