Audrey Ferguson

  • 101

    Democritus - 429 B.C.

    First person to think of the atom. The atom was a solid cirlce.
  • 101

    Aristotle - 400 B.C.

    He discoverd the four elements of life: air, wind, water, fire. His model was a diamond dividing the elements into it's corners.
  • Sir Isaac Newton

    Tiny pieces of mass. His model was a solid circle.
  • John Dalton- 1766-1844 (Theory dev. in 1803)

    Dalton's Atomic Theory.
    All matter is composed of atoms (T)
    Atoms can't be made or destroyed (F)
    Atoms of same elements are identical (T)
    Different elements=different atoms (T)
    Model: circle (not filled in)
    Chemical reactions occur when atoms are rearranged (F)
    Compounds are formed from atoms of different elements (T)
  • Henri Becquerel

    Discovered radioactivity
    Model:solid circle
  • JJ Thomson

    Discovered electrons
    Model: Cirlce containing negatively charged electrons and positively charged protons
    Cathode Ray Tube
  • Millikan

    Measured charge and mass of an electron
    Model: negatively charged electrons and a large cross through the center
  • Rutherford

    Atom has a central positive nucleus surrounded by nagative orbiting electrons
    Model: negatively charged electrons surrounding a positive nucleus
  • Niels Bohr

    electrons in orbit
    positively charged nucleus Model contains 3 rings and a dot in the middle
  • Aston

    mass spectrometer
    discovered isotopes Model: 2 rings and a colored in circle in the middle
  • Shrodinger

    Atomic Model
    Atom consists of clouds and nucleus
    Discovered formula
    Calculated odds of where an electron might be
    Proved Bohr wrong
  • James Chadwick

    Discovered the neutron Model: vertical and horizontal rings connected through the center