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500
Democratis Formulated an Atomic Theory for the Cosmos
Theorizes that the world consists of two fundemental parts invisible atoms and an empty void -
Period: 500 to
History of the Atomic Theory
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Dalton
His theory stated that all mattr is made of atoms, and those atoms are indivisible and industructable. It also stated that all atoms of a given element are identical in mass and properties. His thoery also said that compounds are formed by two or more different atoms, and that a chemical reaction is a rearrangement of atoms. -
Thomson
Theory stated that an atom is a positivley charged sphere with negatively charged electrons floating inside it. This reminded him of plum pudding so it was named the plum pudding model. -
Millikan
Determined the unit charge of an electron with his oil drop experiment. Thus allowing for the calculation of the mass of an electron and the positively charged atoms ( e=1.60x10 to the -19 power -
Rutherford
Thoery described an atom as having a central positive nucleus surrounded by orbiting negative electrons. -
Bohr
Theory depicts an atom as a small, positively charged nucleus surrounded by electrons that travel in circular orbits around the nucleus -
Modern (Louis - Victor Pierre Raymond de Broglie
A french prince who generalized Einstein's work from the specific case of light to cover all other types of particles. His Thoery stated that electrons were in the form of waves not particles. -
Aristotle
Made a Theory that all mater was made up of four elements. Air, Water, Fire, and Earth
