-
400
Aristole
Aristole stated that all subtances are made up of four elements which are: Air,Earth, Fire, and Wind -
400
Democritus
Democritus proposed that all matter incliding air and space is made up of atoms. -
John Dalton
Transformed ideas of an atom into a compound -
J.J Thompson
Thompson discovered the electron and to prove his statement he used th Cathode Ray tube Experiment. -
Robert Millikan
Determind the charge and size of the elctron. Using the Oil Drop Experiment. -
Ernest Rutherford
Ernest Rutherford discovered the alpha and beta rays. -
Neils Bohr
Proposed that an energylevel is found only in specifc circular paths, or orbits around the electrons -
Sir James Chadwick
Confirmed the existences of the neutron to the atomic theory
