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History of the atom
How the theories and the models of the atom change over time
| Term | Definition |
|---|---|
| John Dalton - 1800 | Set the base for the idea of the atom, saying that everything is made of tiny indivisible balls, which his idea wasn't accepted at the time |
| J.J Thompson - Plum pudding model - 1897 | Developed the theory of atoms, and made a model, were there were randomly dotted electrons, in a positively charged cloud, that looked like plum pudding |
| Rutherford - gold foil experiment - 1909 | He fired alpha particles at a sheet of gold foil, expecting them to go straight through, nut there were a few that bounced back, which he concluded that atoms were made of a positive nucleus with empty space around it |
| Neils Bohr - 1911 | Discovered that there are electrons orbiting the nucleus of the atoms in shells |
| James Chadwick - 1940 | Discovered neutrons in the nucleus of the atom |