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Atomic Structure Timeline

By dtarbox
  • Idea of the Atom
    100

    Idea of the Atom

    It was discovered by Democritus In 440 BC but the website won't let me set it to 440 BC
  • Daltons atomic theory

    Daltons atomic theory

    Dalton theory on the Atom
  • Discovery of Electrons

    Discovery of Electrons

    Experiments by J.J. Thomson in 1897 led to the discovery of a fundamental building block of matter
  • Discovery of the nucleus in an Atom

    Discovery of the nucleus in an Atom

    The nucleus is the very dense region consisting of protons and neutrons at the center of an atom. Discovered by Ernest Rutherford
  • Discovery of Protons

    Discovery of Protons

    Shortly after the World War I, in 1920, Rutherford proposed the name proton for the positively charged particles in the nucleus of an atom
  • Electron orbitals, shells and clouds

    Electron orbitals, shells and clouds

    Niels Bohr described atomic structure and the presence of orbital shells. The atomic model consisted of successive shells, in which the electrons were arranged
  • Discovery of Neutrons

    Discovery of Neutrons

    It is remarkable that the neutron was not discovered until 1932 when James Chadwick used scattering data to calculate the mass of this neutral particle