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    Rb

    Rubidium

    Alkali Metal

    Atomic Number: 37 • Atomic Mass: 85.4680 u • Period: 5 • Group: 1

    Electron Configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s¹
    Phase: Solid
    Electronegativity: 0.82
    Krypton (Kr)Strontium (Sr)
    OverviewPropertiesAtomic StructureOccurrenceApplicationsHistory

    Overview

    Rubidium is the chemical element with the symbol Rb and atomic number 37. It belongs to the Alkali Metal group and is located in period 5 of the periodic table. It exists as a solid under standard conditions.

    Basic Information

    • Symbol:Rb
    • Atomic Number:37
    • Atomic Mass:85.4680 u
    • Group:1
    • Period:5
    • Category:Alkali Metal
    • Phase at STP:Solid
    • Electronegativity:0.82 (Pauling scale)

    Key Facts

    Fun Fact #1

    Ignites spontaneously in air

    Fun Fact #2

    Can be liquid at room temperature

    Common Uses

    • Atomic clocks
    • Electronics
    • Medical imaging