| A. | Dalton | | There are positively charged particles in atoms. |
| B. | Bohr | | Electrons move around the nucleus in orbit patterns. |
| C. | Rutherford | | All matter is made of atoms. |
| D. | De Broglie and Schrödinger | | Electrons are in a cloud around the nucleus. |
| E. | Chadwick | | Neutrons exist. |
| F. | Mendeleev | | The periodic table is organized by atomic number. |
| G. | Moseley | | The periodic table is organized by atomic mass. |