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    Cl

    Chlorine

    Halogen

    Atomic Number: 17 • Atomic Mass: 35.4500 u • Period: 3 • Group: 17

    Electron Configuration: 1s² 2s² 2p⁶ 3s² 3p⁵
    Phase: Gas
    Electronegativity: 3.16
    Sulfur (S)Argon (Ar)
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    Physical & Chemical Properties

    Physical Properties

    • •Yellowish-green gas at room temperature
    • •Pungent, irritating odor
    • •Heavier than air
    • •Moderately soluble in water to form hypochlorous acid and hydrochloric acid
    Melting Point

    171.6 K (-101.55 °C, -150.79 °F)

    Boiling Point

    239.11 K (-34.04 °C, -29.27 °F)

    Density

    0.003214 g/cm³

    Electronegativity

    3.16 (Pauling scale)

    Chemical Properties

    • •Strong oxidizing agent
    • •Highly reactive halogen
    • •Forms compounds with most elements
    • •Can exist in oxidation states from -1 to +7

    Electron Configuration

    1s² 2s² 2p⁶ 3s² 3p⁵

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