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A LITTLE SOMETHING WORTH KNOWING

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Oxygen · chemical symbol

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Oxygen gas makes up about one fifth of dry air near Earth's surface. Source: Oxygen ↗

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More from The Elements

A few more worth knowing.

  1. 09This element is a soft reactive metal that combines with chlorine to form ordinary table salt.RECALL
    Sodium

    Sodium is a soft reactive metal that combines with chlorine to form ordinary table salt.

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  2. 10Sodium · chemical symbolRECALL
    Na

    Sodium is a soft reactive metal that combines with chlorine to form ordinary table salt.

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  3. 11This element burns with a bright white flame and sits at the center of every chlorophyll molecule in plants.RECALL
    Magnesium

    Magnesium burns with a bright white flame and sits at the center of every chlorophyll molecule in plants.

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