Atomic Model Timeline

  • John Dalton

    John Dalton
    John Dalton, an English chemist who proposed the Atomic Theory which stated that all matter was composed of small indivisible particles called atoms.
  • J.J Thompson

    J.J Thompson
    First to measure the electron and developed the plum-pudding model of the atom. It dscribes the atom as a slightly positive sphere with small electrons inside
  • Hantaro Nagaoka

    Hantaro Nagaoka
    Nagaoka rejected Thomson's model. He said an alternative model in which a positively charged center is surrounded by a number of revolving electrons, in the manner of Saturn and its rings. This was called the Planetary Model.
  • Ernest Rutherford

    Ernest Rutherford
    Rutherford's new model for the atom, based on the experimental results, contained the new features of a relatively high central charge concentrated into a very small volume. His model is called the Electron Cloud Model
  • Niels Bohr

    Niels Bohr
    He stated that electrons could only orbit the nucleus in succesively larger orbits around the nucleus. The outer orbits could hold more electrons. The electrons in the outermost shell determine the properties of the atom.
  • Louis de Broglie

    Louis de Broglie
    He believed that electrons can act like both particles and waves, just like light. He also said that waves produced by electrons contained in the orbit around the nucleus, set up a standing wave of a certain energy, frequency, and wavelength. He discovered that electrons can act like waves.
  • Erwin Schrodinger

    Erwin Schrodinger
    Developed wave mechanics which describe the behavior
    of quantum systems for bosons.
  • James Chawick

    James Chawick
    He discovered the nuetron and said that nuetrons were nuetral.