Atom discovery scientists

Bohr

Predicted that electrons travel in specific energy levels

Democritus

First person to identify the possibility of an atom

Dalton

Father of modern atomic theory; five parts of theory include that elements are made of atoms and that element's atoms are identical in mass.

J.J. Thompson

Discovered the electron

R.A. Millikan

Determined the charge and mass of an electron during the oil drop experiment

Rutherford

Said that an atom has a small positive nucleus and the remainder is empty space through the gold foil experiment.

Chadwick

Discovered the neutron.