Atomic Theory!

  • 335


    He lived from 384 BC until 322 BC. He took up from Plato, with some different elements that had been changed. He assumed that any object had four attributes: matter, form, moving cause, and final cause. He was the one who found that heavy things fall faster than lighter things.
  • 400


    He lived from 460 Bc until 370 BC. He believed that everything was the result of natural laws.
  • Period: 400 to

    Atomic Theory

  • John Dalton

    John Dalton
    Lived from 1760 until 1844. He pictured atoms as tiny, indestructible particles, with no internal structure. He made wooden spheres with different masses to prove his theory.
  • J.J Thompson

    J.J Thompson
    He lived from 1856-1940. He pictured electrons embedded in a sphere of positive electric charge. To prove this, he plugged a wire into a source of electirc currents and both ends (+,-) of a sealed tube filled with gas at low pressure.
  • Hantaro Nagaoka

    Hantaro Nagaoka
    He lived from 1865 until 1950. He believed and atom has a central nucleus, and that electrons move in orbits like the rings around Saturn. He made two predictions, then continued to create the Saturnian model.
  • Ernest Marsden

    Ernest Marsden
    He lived from 1889 until 1970. He ALSO conducted the gold foil expirement which is alos known as the Geiger-Marsden expirement.
  • Ernest Rutherford

    Ernest Rutherford
    He lived from 1871 until 1937. He said and atom has a dense, positively charged nucleus and that electrons move randomly in the space around the nucleus. He did the gold foil expirement, which showed the deflected and undeflected particles.
  • Niels Bohr

    Niels Bohr
    He lived from 1885 until 1962.He said that the electrons move in spherical orbits at fixed distances from the nucleus. His expirement was the subshell model.
  • Max Planck

    Max Planck
    He lived from 1858 until 1947. He used the idea of quanta (discrete units of energy) to explain hot glowing matter.
  • Louis de Broglie

    Louis de Broglie
    He lived from 1892 until 1987.He proposed that moving particles like electrons have some properties of waves. There was even evidence of this!
  • Erwin Schrodinger

    Erwin Schrodinger
    He lived from 1887 until 1961. He used many mathematical equations.
  • Enrico Fermi

    Enrico Fermi
    He lived from 1901 until 1954. He conducted the first controlled chain reaction releasing energy from the atoms nucleus.
  • James Chadwick

    James Chadwick
    He lived from 1891 until 1974. He found the neutron which has a lack of electrical charge. Unlike positively charged alpha particles, the neutrons dont need to overcome any Coulomb barrier, making it able to split the nuclei of even the heaviest elements.