-
500 BCE
Democritus proposal
Democritus proposed the existence of atoms -
Dalton's developed theory
Dalton developed his theory of atoms and matter. -
The discovery of Electron
JJ Thompson discovered the electron. -
The development of the planetary model
Rutherford developed the planetary model of the atom. -
Development of a model of the atom
Bohr developed a model of the atom. -
Proton discovery
The proton was discovered -
Neutron's discovery
The neutron was discovered 13 years after the proton was discovered
