history of atomic model

By ryanfur

  • John Dalton

    Proposed an "atomic theory" with spherical solid atoms based upon measurable properties of mass.

  • J.J Thomson

    Studied "canal rays" and found they were associated with the proton H + .

  • J.J Thomson

    Used a CRT to experimentally determine the charge to mass ratio (e/m) of an electron =1.759 x 10 8 coulombs/gram.

  • Ernest Rutherford

    Using alpha particles as atomic bullets, probed the atoms in a piece of thin (0.00006 cm) foil of gold. He established that the nucleus was: very dense,very small and positively charged. He also assumed that the electrons were located outside the nucleus.

  • Niels Bohr

    Developed an explanation of atomic structure that underlies regularities of the periodic table of elements. His atomic model had atoms built up of sucessive orbital shells of electrons.