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1.2: Compounds and Molecules

  • Page ID
    2172
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    A molecule is formed when two or more atoms join together. A compound is formed when two or more different elements combine in a fixed ratio by mass. Note that some atoms are never found alone. For example oxygen is always found as molecules of 2 oxygen atoms (represented as O2).

    The table below gives some common compounds.

    Compound Symbol
    Calcium carbonate CaCO3
    Carbon dioxide CO2
    Copper sulphate CuSO4
    Glucose C6H12O6
    Hydrochloric acid HCl
    Sodium bicarbonate (baking soda) NaHCO3
    Sodium chloride (table salt) NaCl
    Sodium hydroxide NaOH
    Water H2O

    This page titled 1.2: Compounds and Molecules is shared under a CC BY-SA 3.0 license and was authored, remixed, and/or curated by Ruth Lawson via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.