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    F

    Fluorine

    Halogen

    Atomic Number: 9 • Atomic Mass: 18.9980 u • Period: 2 • Group: 17

    Electron Configuration: 1s² 2s² 2p⁵
    Phase: Gas
    Electronegativity: 3.98
    Oxygen (O)Neon (Ne)
    OverviewPropertiesAtomic StructureOccurrenceApplicationsHistory

    Overview

    Fluorine is the chemical element with the symbol F and atomic number 9. It belongs to the Halogen group and is located in period 2 of the periodic table. It exists as a gas under standard conditions.

    Basic Information

    • Symbol:F
    • Atomic Number:9
    • Atomic Mass:18.9980 u
    • Group:17
    • Period:2
    • Category:Halogen
    • Phase at STP:Gas
    • Electronegativity:3.98 (Pauling scale)

    Key Facts

    Fun Fact #1

    Most reactive non-metal

    Fun Fact #2

    Most electronegative element

    Common Uses

    • Toothpaste
    • Teflon
    • Refrigerants