Scientists that contributed to the model of the atom

By jordan.greenwell
  • 350

    Aristotle

    He thought that there were only 4 elements, fire, water, air, and earth. (Also BC)
  • 400

    Democritus

    Everything is made up of atoms (this is supposed to be in BC but I cant figure how to)
  • 500

    Parmenides

    He thought that everything was made up of blocks (supposed to be in BC)

  • John Dalton

    1. All elements are composed of atoms
    2. atoms of the same element are the same, atoms of differnet elements are different
    3. Atoms of different elements can physically and chemically mix to form compounds
    4. Chemical change does not mean atomic change or they are not destroyed.

  • JJ Thomson

    Discovered electrons existence but not details, cathode ray tube

  • Milikan

    Found charge and mass of electron, mass of atom

  • Gold Foil Experiment

    Shot alpha particles at gold foil. They should have gone straight through but some bounced off showing that there was a nucleus

  • Niels Bohr

    Electrons orbited in rings, could jump from orbit to orbit to emit energy

  • James Chadwick

    Discovered the nuetron

  • The manhattan project

    Nuclear research created atomic bomb for WWII, seperated the atom.