Atom, the smallest unit that matter can be broken down into without releasing any electrically charged particles. Atoms are also the smallest unit of matter that exhibit the characteristic properties of an element. As such, the atom is the fundamental building block for chemistry.
Example: Ne, O
A molecule can be defined as the combinations of two or more atoms which are held together by chemical bonds. A molecule is the smallest portion of a substance which showcases all the properties of the substance. On breaking down a molecule further, we see properties of the constituent elements.
Example: O2, HCl
Let us discuss the differences between atoms and molecules.
| Factor | Atoms | Molecules |
| Definition | Most fundamental and smallest part that can exist of an element. | Two or more atoms chemically bonded together. |
| Example | Oxygen – O |