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450
Democritus
B.C.- Came up with the idea that atoms can not be split. -
450
Aristotle
450 B.C.-Unlike his buddy Democritus, Aristotle did not believe an atom existed, but the true idea came around 2000 years later. -
Period: 450 to
History of the Atomic Theory
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Antoine Lavoisier
Founded the law of conservation of matter. He also states that there are 3 states of aggregation. Matter cannot be created or destroyed. -
Joseph Proust
Came up with the idea that atoms have different weights. (Protons, Neutrons, Electrons) -
John Dalton
founded law of Multiple Proportions. Atoms have different ratios to combine to form mixtures. Society did not accept his beliefs for a while longer. -
J.J. Thomson
Discovered atoms have negative charges called electron. One of the main compunds of the modern atomic structure. -
Robert Millikan
Discovered the value for a negative charge through the oildrop experiment. He also helped discovered with J.J. Thomson that electrons are negative. -
Niels Bohr
Theory that atom was 1/10000 the size of other scientists atoms. Atoms are TINY, and act like orbit like planets. -
Ernest Rutherford
Proved that an atom has a nucleus and that is surrounded by negative electrons. Discovered basic atomic structure.