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460
Democritus
greek philosopher
atoms cannot be divided
was credited with naming particles atoms
believed that atoms:infinite number
always moving
could combine with others
each substance had atoms
http://www.iep.utm.edu/democrit/ -
Period: 460 to
it starts at 460 B.C.
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John Dalton
based his theory on experiments
all matter is made of atoms and are indivisibole and indestructable
all atoms of a given element are identical in mass and properties
a chemical is a rearrangemant of atoms
atoms can neither be dcreated nor destroyed
http://www.biography.com/people/john-dalton-9265201 -
J.J Thomson
Lived form 1856-1940
won the nobel prize in physics in 1906
used the cathode ray tube
proposed a model similar to a chocalate chip cookie
http://www.nobelprize.org/nobel_prizes/physics/laureates/1906/thomson-bio.html -
Ernest Ruutherford
former student of Thomson's
won a nobel prize in chemistry in 1908
found that Thomsons atomic model was incorrect
used gold foil to determine that the positive charge was located in the nucleus and that most of the atom was empty space
http://www.nobelprize.org/nobel_prizes/chemistry/laureates/1908/rutherford-bio.html -
Niels Bohr
won nobel prize in physics in 1922
proposed that electrons orbit the nucleus, could only move in fixed orbites of specific energies, and that electrons with low energy would orbit closer to the nucleus than the ones with higher energy
http://www.nobelprize.org/nobel_prizes/physics/laureates/1922/bohr-bio.html -
Erwin Schrodinger
born in Vienna, Austria
won nobel prize in physics in 1933
quantum mechanics
the electrons absorb and emit radiation of fixed wavelengths when jumping between the fixed orbits around a nucleus
http://www.nobelprize.org/nobel_prizes/physics/laureates/1933/schrodinger-facts.html
