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    Cs

    Cesium

    Alkali Metal

    Atomic Number: 55 • Atomic Mass: 132.9100 u • Period: 6 • Group: 1

    Electron Configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s¹
    Phase: Solid
    Electronegativity: 0.79
    Xenon (Xe)Barium (Ba)
    OverviewPropertiesAtomic StructureOccurrenceApplicationsHistory

    Overview

    Cesium is the chemical element with the symbol Cs and atomic number 55. It belongs to the Alkali Metal group and is located in period 6 of the periodic table. It exists as a solid under standard conditions.

    Basic Information

    • Symbol:Cs
    • Atomic Number:55
    • Atomic Mass:132.9100 u
    • Group:1
    • Period:6
    • Category:Alkali Metal
    • Phase at STP:Solid
    • Electronegativity:0.79 (Pauling scale)

    Key Facts

    Fun Fact #1

    Most electropositive element

    Fun Fact #2

    Liquid at room temperature

    Common Uses

    • Atomic clocks
    • Oil drilling
    • Photoelectric cells