Atomic Theory Through the Ages

By J&DM4
  • Jan 1, 1000

    Democritus

    Democritus
    Democritus(460-370 B.C) First person to suggest that matter could not be infinitely divided.
  • Feb 1, 1001

    Aristotle

    Aristotle
    Aristotle (384-322 B.C) Disagreed with Democritus' idea that atoms move through empty space. His ideas about matter took over those of Democritus- back to square one.
  • Mar 1, 1002

    Dalton

    Dalton
    John Dalton (1776- 1844) English schoolteacher who marks the beginning of the developement of modern atomic theory. Took Democritus' ideas about matter and revised them based off of his personal scientific research.
  • Mar 2, 1002

    Conservation Of Mass

    Conseravtion of Mass (490-430 B.C) Atoms can rearranged, seperated, or combined to form new things, but cannot be created, destroyed, or divided in the process.
  • Mar 3, 1002

    The Atom

    The Atom
    The Atom (1800s) Since the adoption of Dalton's atomic theory, the existence of atoms has been scientifically proven.
  • Aug 25, 1003

    The Cathode Ray Tube

    The Cathode Ray Tube
    The Cathode Ray Tube (1869). Matter and electric charge must be related. Glass tubes with air removed from the inside chamber connected to an electric source via a cathode and an anode.
  • Aug 30, 1003

    The Mass and Charge of an electron

    The Mass and Charge of an electron
    J.J Thompson(1856-1940) designed a series of CRT experiments at Cambridge to find the ratio of the partices to change the mass.Thompson received the nobel prize in 1906 for his research- discovery of the electron, the first subatomic particle.
  • Aug 26, 1004

    The mass and charge of the electron

    The mass and charge of the electron
    Physicist Robert Millikan (1868-1953) designed an oil drop apparatus to determine the charge of the electron.
  • Aug 26, 1004

    Golf Foil Experiment

    Golf Foil Experiment
    Ernest Rutherford studied how positvely charged a-particles interacted with solid matter. He designed an experiment to see if a-particles would be deflected as they passed through a thin sheet of gold.
  • Aug 29, 1004

    The Nucleus

    The Nucleus
    BAsed on the results of his gold foil experiment, Rutherford calculated that an atom was mostly just empty space for electrons to move around it. There hadto be a place for the positive charge and the majority of the mass of an atom to reside. He claimed that it was contained in a tiny region in the center of the atom. That spot was called the nucleus.