History of the Atomic Model

By Isabella.saltos
  • 500 BCE

    Democritus

    Democritus
    Democritus proposed the existence of atoms. Due to the limited technology at the time, his idea could not be tested.

  • Dalton

    Dalton
    In 1804, Dalton then developed his theory of atoms and matter. After experiments in chemistry, Dalton was able to support his hypothesis with evidence.

  • JJ Tomson

    JJ Tomson
    JJ Tomson discovered the electron. He experimented using electric charges in cathode ray tubes.

  • Rutherford

    Rutherford
    Rutherford developed the planetary model of the atom. Rutherford experimented using alpha particles fired at thin gold foil. An early prototype of a 'Geiger counter' was used to measure results.

  • Bohr

    Bohr
    Bohr developed a model of the atom. Using mathematical models and laws of quantum physics, Bohr developed his updated model.

  • James Chadwick

    James Chadwick
    James Chadwick discovered the neutron. He experimented using kinematics and accurate measurements, which lead him to discover the neutron.