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Period: 100 to
Atomic Theory Timeline
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300
Aristotle's Theory
(300)
Aristotle began the idea for elements such as
Earth, Water, Air, Fire, and Aether, which is "heavenly" objects/substances. -
400
Democritus' Theory
(400 BC)
Democritus created the idea of "atoms" which was highly disaproved of by the people of his time. -
John Dalton's Atomic Theory
(Exact Date was not found)
Dalton had 5 Points in his theory:
1.That atoms were small particles that made up elements.
2.Atoms in an element are identical in mass, size, and other properties, but are not equal to other element's atoms.
3.Atoms are unable to be divided
4.Elements can be combined to make chemical compounds.
5.Elements are combined, seperated or rearranged in a chemical compound. -
Marie Curie's Discovery
Marie Curie discovered "radioactivity", which were techniques to isolate radioactive isotopes and discovered polonium and radium. (she later died of radioactivity, oh the irony.) -
JJ Thomson's "Plum Pudding" Model
JJ Thomson's Model added the electron to the atomic model. -
Rutherford's Model
Rutherford's model disproved Thomson's model with his own, making changes to the atomic figure -
Bohr's Model
Bohr's model suggested the idea of the nucleus having the electrons orbit like planets around the sun. -
Electron Cloud Model
In 1925, Erwin Schrödinger and Werner Heisenberg created a more accurate version of the atomic model that did not predict the position, but the behavior. -
Chadwick's Discovery
Chadwick discovered the Neutron, which won him a nobel prize. -
George Zweig
George Zweig suggested the existence of quarks.
