Hoyo-McCauley-Per 3

  • 500


    Aristotle develops his theory stating that no matter how many times you divide matter there will always be a piece of matter that is smaller.
  • 500


    States that all matter is made up of tiny, invisible, indivisible particles called atoms.
  • Period: 500 to

    The History of The Atom

  • James Dalton

    Dalton formed the theory that all matter is composed of small particles called atoms. These atoms were said to all be the same
  • Henri Becquerel

    Henri Becquerel discovers some chemicals desintigrate with the effects of x-rays. He discovered radioactivity.
  • Marie and Pierre Curie

    The duo started experimenting with radioactive substances and discovered radium and polonium.
  • J.J Thomson

    Discovered the electron and put together the plum pudding model.
  • Robert Millikan

    Millikan discovered the electric charge in an electron.
  • Ernest Rutherford

    After Rutherfords gold foil experiment he discovered the possitive charge at the center of an atom.
  • Niels Bohr

    Niels Nohr develops an explaination of the atomic structure that became the basis of the periodic table.
  • James Chadwick

    Chadwick used alpha particles to discover the neutron.