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A molecule is formed from two or more atoms of a single element. An example is h2o. two hydrogen atoms and one oxygen atom forming a molecule of water! This question is archived.
Answer in words: 1  Elements can consist of either atoms or molecules but if molecules then those molecules are formed only from atoms of the same type (that is, atoms of the same element).  Mixtures can consist of either atoms or molecules - but must include at least two different atoms or molecules.