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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)
    OverviewPropertiesAtomic StructureOccurrenceApplicationsHistory

    History

    Oxygen has been known since ancient times

    Historical Timeline

    Independently discovered by Priestley in 1774 and Scheele in 1772

    Named by Antoine Lavoisier in 1777

    Identified as an element during the Chemical Revolution

    First isolated by electrolysis of water in 1800 by William Nicholson and Anthony Carlisle