Final answer:
A molecule of water consists of two hydrogen atoms bonded to one oxygen atom, while the substance water refers to the collection of multiple water molecules.
Step-by-step explanation:
A molecule of water refers to a single unit of water, which consists of two hydrogen atoms bonded to one oxygen atom. On the other hand, the substance water refers to the collection of multiple water molecules, typically in the liquid state at room temperature and atmospheric pressure. So, while a molecule of water is a specific arrangement of atoms, the substance water represents a larger quantity of these molecules.
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