The evolution of the atomic model has taken many years and the contributions of many scientists.
To the right, you will find a summary of the major scientists' contributions to our current understanding of the structure of the atom. Even though the first four were proven incorrect, they all provided essential advances to the current model.
1 Dalton: Billiard-Ball Model (the atom is the smallest unit of nature).
2 Thomson: Plum Pudding Model (the discovery of the electron).
3 Rutherford: the Planetary Model (the atom contains a small positive nucleus surrounded by mostly empty space)
4 Bohr: Electron Shell Model (the electrons are found in fixed energy states surrounding the nucleus)
5 Modern: Wave-Mechanical Model (the electrons are found in orbitals surrounding the nucleus)
