Danielle Rine Famous Dead Guy Timeline

By danielle.rine
  • 101

    Democritus 429 BC

    First person to think of the atom.
    Thought the atom was a solid circle.
  • 101

    Aristotle 400 BC

    Proposed that everything was made of fire, earth, air , and water instead of atoms.

  • Isaac Newton

    Believed that there were little tiny pieces of mass that were swimming everywhere.

  • John Dalton

    Made the Atomic Theory.
    all matter is composed of atoms (T)
    atoms cannot be made or destroyed (F)
    atoms of the same elements are identical (F)
    different elements have different types of atoms (T)
    chemical reactions occur when atoms are rearranged (T)
    compounds are formed from atoms of different elements (T)

  • Henri Becquerel

    Helped discover radioactivity.

  • Joseph John Thomson

    Proved the existence of negatively charged particles, later called electrons

  • Millikan

    Measured the charge and mass of a single electron.

  • Rutherford

    An atom has a central positive nucleus surrounded by a negative orbiting nucleus.
    Credited with nucleus and also the proton.

  • Niels Bohr

    Depicted atom as small, positively charged nucleus surrounded by electrons.
    Electrons traveling in circular orbits.

  • Francis Aston

    Discovered isotopes of non-radioactive elements.

  • Erwin Schrodinger

    Discovered the formula that calculated the odds of where an electron migth be.
    Atom consists of nucleus and clouds.
    Proved Bohr model incorrect.

  • James Chadwick

    Discovered the neutron.