Atomic Theory Time Line

By ant8876
  • Jan 1, 1000

    Democritus

    was the first person to come up with the thought of a piece of matter that can't be divided into smaller parts, he called this the atom.

  • John Dalton

    Developed an atomic theory stating that spherical atoms had measurable properties of mass.

  • J.J. Thompson

    Discovered the electron while using the cathode ray tube, to determine the charge to mass ratio of an electron.

  • Ernest Rutherford

    Performed the gold foil experiment to determine that the nucleus is a small, dense, , and positively charged part of the atom, based on the assumption that electrons are on the outside of the nucleus.