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460
460 BC Democritus develops the idea of atoms
460 BC-he pounded up materials in his pestle and mortar until he had reduced them to smaller and smaller particles which he called -
1808 John Dalton
suggested that all matter was made up of tiny spheres that were able to bounce around with perfect elasticity and called them -
1898 Joseph John Thompson
found that atoms could sometimes eject a far smaller negative particle which he called an -
1904 Thompson
Thompson develops the idea that an atom was made up of electrons scattered unevenly within an elastic sphere surrounded by a soup of positive charge to balance the electron's charge -
1910 Ernest Rutherford
oversaw Geiger and Marsden carrying out his famous experiment. They fired Helium nuclei at a piece of gold foil which was only a few atoms thick. They found that although most of them passed through. About 1 in 10,000 hit