1. Atoms are singular
Molecules are 2 or more combined atoms
2. Atoms are not bonded
Molecules are atoms that are bonded
3. Atoms is some thing which can't be split
Molecule can be divided into many atoms.
4. Atom consists of protons, neutrons and electrons.
Molecule is combination of mixture of atoms like H2O, H2, N2, NaCl, NaK, Etc.