Believed in five elements Earth, Water, Fire, Air, Aether- planets , sun, stars
Believed all matter consisted of extremely small particles that could not be divided
Came up with the first atomic theory
Discovered the electron was negitive
Conducted an Experiment to determin the mass of the electreon.He placed drops between an electrical feild and determined the precise mass of an electron at 1\1837.
Proposed the orbital view of the atom
He won the nobel prize for discovering the neutron. The neutron is neutral and has a mass of 1.008665 amu or simply 1.