Back to Elements
    Ar

    Argon

    Noble Gas

    Atomic Number: 18 • Atomic Mass: 39.9480 u • Period: 3 • Group: 18

    Electron Configuration: 1s² 2s² 2p⁶ 3s² 3p⁶
    Phase: Gas
    Electronegativity: 0
    Chlorine (Cl)Potassium (K)
    OverviewPropertiesAtomic StructureOccurrenceApplicationsHistory

    Physical & Chemical Properties

    Physical Properties

    • •Colorless, odorless, tasteless gas
    • •Slightly soluble in water
    • •Inert under most conditions
    • •Condenses to a colorless liquid at low temperatures
    Melting Point

    83.8 K (-189.35 °C, -308.83 °F)

    Boiling Point

    87.3 K (-185.85 °C, -302.53 °F)

    Density

    0.0017837 g/cm³

    Electronegativity

    0 (Pauling scale)

    Chemical Properties

    • •Extremely unreactive due to full valence shell
    • •Forms few compounds under extreme conditions
    • •First noble gas to have a confirmed compound (argon fluorohydride)
    • •Stable against chemical combination

    Electron Configuration

    1s² 2s² 2p⁶ 3s² 3p⁶

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