Development of Atomic theory

  • Period: 400 BCE to 400 BCE

    400 BC

    Democritus named these tiniest particles of matter “atomos” which was the greek word for “unable to divide”.
  • Period: to

    1807

    John Dalton is considered to be a pioneer of modern atomic. He experimented on gases to learn more about them and the particles they are made of.
  • Period: to

    1903

    JJ Thomson Experimented with electric charges and cathode ray tubes. He said that the glow produced in the tube when electricity passed through was a negatively charged particle to be parts of the atom itself.
  • Period: to

    1911

    Rutherford’s version of the atom came as the result of experiments in which he found positive charges at gold atoms.
  • Period: to

    1913

    Niels Bohr stated that if Rutherford's model of the atom was correct, it would be very unstable and the matter would fall apart. Bohr's model of the atom was very complicated.
  • Period: to

    1932

    In 1932, Chadwick found proof of the existence of another type of particle in the nucleus. Chadwicks model of the atom is the most consistent.