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    Ca

    Calcium

    Alkaline Earth

    Atomic Number: 20 • Atomic Mass: 40.0780 u • Period: 4 • Group: 2

    Electron Configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s²
    Phase: Solid
    Electronegativity: 1
    Potassium (K)Scandium (Sc)
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    Physical & Chemical Properties

    Physical Properties

    • •Silvery-white, relatively soft metal
    • •Fifth most abundant element in Earth's crust
    • •Melting point of 1115 K (842°C)
    • •Readily oxidizes in air forming a protective layer
    • •Medium density of 1.54 g/cm³
    Melting Point

    1115 K (841.85 °C, 1547.33 °F)

    Boiling Point

    1757 K (1483.85 °C, 2702.93 °F)

    Density

    1.54 g/cm³

    Electronegativity

    1 (Pauling scale)

    Chemical Properties

    • •Reacts with water to produce hydrogen gas and calcium hydroxide
    • •Forms ionic compounds with many non-metals
    • •Predominantly exists in the +2 oxidation state
    • •Essential element for living organisms
    • •Important component in shell formation and bone structure

    Electron Configuration

    1s² 2s² 2p⁶ 3s² 3p⁶ 4s²

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