When a molecule is broken down into its constituent atoms, these atoms do not have the same properties as the molecule.
We can use an everyday molecule, such as water, H20, to show this property. Water is a liquid with unique properties that stem from its hydrogen bonding. On the other hand, its constituent atoms, hydrogen and oxygen, are not liquids, and have very different properties. Oxygen and hydrogen are both gases; hydrogen is dangerous and very flammable, while we breathe in oxygen throughout our lives. This example illustrates how the atoms that make up a molecule usually have different properties than the completed molecule.
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