Atom&Molecules

Atom is the smallest particle of an element which can take part in a chemical reaction. It mayor may not be capable of independent existence.

Molecule is the simplest particle of matter that has independent existence. It may be homoatomic e.g., H₂, CI₂, N₂ (diatomic), O3(triatomic) or heteroatomic, e.g., HCI, NH₃, CH₃ etc