chemistry timeline, Ryan p.

Events

Democritus

400 B.C.

Democritus developed the theory of atoms, believed the atom was an extremely small ball

john Dalton

1803

newly possible experiments with gas led to Dalton developing his theory of atoms, he still believed atoms looked like billiard balls

Robert Millikan

1909

he identified the charge of an electron model while doing his oil drop expirement

Ernest Rutherford

1911

found that the nucleus of an atom is positively stared through his gold foil experiment, developed the plum pudding model

Niels Bohr

1913

he developed the theory that electrons moved around the nucleus

Werner Heisenberg

1925

brought the idea of quantum physics and the idea of an electron cloud

Erwin Schrodinger

1926

reinvented the Bohr model to describe the likelihood of finding an electron, developed the quantum mechanical model

James Chadwick

1932

discovered the neutron while bombarding elements with alpha waves