Atoms | Molecules |
Atoms may be defined as the smallest particle of an element which does not exist free in nature . | Molecule may be defined as the smallest particle of an element or compoundwhich exists free in nature |
For example, the hydrgen atom is represented by H,the sodium atom is represented by Na, etc. |
For example,water molecules are represented by H2O .It says that each water molecule contains two atoms of hydrogen and one atom of oxygen. |