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Period: 460 BCE to 370 BCE
Democritus
He propose matter was not infinitely divisible, he said atoms could not be created or destroyed.He's ideas were not well accepted by other philosophers. -
Period: 384 BCE to 322 BCE
Aristotle
He thought empty space exist. He thought matter is made of earth, fire, air and water -
Period: to
Lavoisier
He was born in France, he work as a scientist, he discovered that mass is conserved in a chemical reaction. He was considered the first scientist and he stablished that matter isn't destruct only change the form. -
Period: to
Dalton
Born on England and work as a teacher in a quicker wording school in Kendal. Dalton took ideas from Democritus and Aristotle and made the first model of atom. It happened the independence of Mexico. -
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Döbereiner
He was a profesor in the Jena university. He discover the triadas of elements. During these time Napoleon its the emperor of France(1804), also Guerrero was founded(1849). -
Period: to
Meyer
Was a Aleman doctor. He discover the periodic law. During 1830 the paid of external deuda was canceled. During 1830 Fernando VIII gets back to the throne in Spain. -
Period: to
Mendeleev
Was a professor of chemistry. He discovers the periodic law. During 1850 was the Italian unification. In Mexico in 1900 Porfirio Putin service an electrical trenvia. -
Period: to
Newlands
He order the 62 elements that were known at that time by the atomic mass of each element. He was a British Chemist. There was a wave of panic in US (1837). In Mexico there was a centralist form of goberment (1837). -
Period: to
Thompson
Realize the experiment of cathode ray tube and discover that the electrons have negative charges. He was born on England and work as a professor of physics in the social royal society. -
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Plank
He was born in Germany and he was a scientist. He discovered that energy is emitted from a black body in discrete amounts called quanta. -
Period: to
Rutherford
He was born in New Zealand and was a physic a chemist. He discovered that atom has a nucleus and discover that the nucleus its the only solid part of an atom.He also discover the proton. There was a revolution in Mexico. -
Period: to
Bohr
He was born in Denmark and work as a physic. His model of atom was the first that incorporated quantum theory. World War develop. -
Period: to
Moseley
He discover the atomic number of each element using x rays. He was killed in work war 1. During that time world war start. In Mexico there were several changes. -
Period: to
James Chadwick
He was born in England and he was a professor on the Cambridge University. He prove the existence of neutrons he help for the creation of the atomic bomb. -
Period: to
Heisenberg
Was born in Germany, he said that atom can't be in a determined speed. World War 2 begins.