Atom is the smallest unit, which is neither be created nor be destroyed.
But, nowadays, Uranium is split-ted to give energy.
Molecules are the group of atoms.
For example, Oxygen is an atom.
But, O₂ is a molecule.

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thank you, pls mark it as berainlierst
The smallest unit of matter is called atom.
many atoms of one or more element combine together to form molecules.
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