-
101
Thales- 600 BC
He believed that everything was made of water. -
101
Democritus- 460 BC
First man to believe the atom was made of a circle, thought of the atom. -
101
Aristotle- 400BC
Believed that everything was made of Earth, Air, Fire, and Water which are the main elements./ -
John Dalton
He said matter is atoms, indivisible and indestructible. All atoms of elements are identical, and atoms of different elements are different. They cannot be created or destroyed. -
Antoine Henri Becquerel
Discovered radioactivity and did the Uranium Experiment -
JJ Thompson
Discovered the electron and did the Cathode Ray Tube experiment. -
Millikan
He had the oil drop experiment and determined the charge and mass of the electron. -
Rutheford
He discovered the nucleus and the proton. He also did the gold foil experiment to figure out that some things did not go all the way through the foil and some bounced back which was a nucleus. -
Neils Bohr
Found that the electrons follow a path , mainly found the Bohr model. -
Francis Aston
Mass spectograph and discovered isotopes. -
Erwin Schrodinger
Created Schrodinger model and had the electron clouds. -
James Chadwick
Plum Pudding model
Proved the existance of nuetrons -
Isaac Newton
He had the first physical experiment and contributions are Laws of Motion, Light Spectrum, and thought Democritus was right.