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  -Leucippus was the mentor of Democritus and originally came up with the atomic theory, but it was then adopted by Democritus
 -All matter consists of invisible particles called atoms that are indestructible
 -The particles are solid but invisible, and they are made up from equal elements according to each object
 -They differ in size, shape , and composition
 -Solids are made of small, pointy atoms
 -Liquids are made of big, round atoms
 -Oils are made of fine, small atoms that slip past each other
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  -Theory developed in 1803
 -Born in September 6, 1766
 -Died in July 27, 1844.
 -Studied meteorology and that made him interested in the study of atoms.
 -The theory states that elements are made up from identical atoms for each element.
 -This atoms have the same mass and properties.
 -Stated that compounds were the special fusion of elements.
 -Also said that atoms of different substances have different weights.
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  -Developed theory in 1869
 -Born february 8, 1834
 -Died February 2, 1907
 -Creator of the periodic table of elements.
 -In this Table the elements are organized by their atomic weight and number.
 -With the time more elements were added to the table thanks to constant discoveries.
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  -Developed theory in 1886.
 -Born in September 5 of 1850
 -Died in 25 of December of 1930,
 -He discovered canal rays that are full of ions with a positive charge, basically he discovered protons.
 -Used cathode rays that are the ones emitted by electrons when are in a cathodic vacuum to study electrons.
 -The atomic model was pictured more accurately thanks to him and that he discovered protons.
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  -Developed 1897 the theory.
 -Born December 18, 1856
 -Died 30 of August, 1940
 -In 1904 delivered six lectures about electricity and matter at Yale University.
 -Discovered an atom could be divided which for the past scientist was impossible, also he discovered electrons.
 -Won a Nobel prize.
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  -Developed theory in 1907
 -He was born on August 30, 1871
 -He died on October 19, 1937
 -Started his investigations by studying magnetic properties of iron when exposed to High-Frequency Discharges
 -Discovered the nucleus of the atom.
 -Most of his books were about atoms.
 -Proposed the nucleus was made of protons(positive charges) and neutrons, while the electrons that were negative surrounded it.
 -Won Nobel Prize of Chemistry.
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  -Developed theory in 1913
 -Born in October 7, 1885
 -Died in November 18, 1962
 -In Cambridge university he worked in a laboratory leadered by J.J Thomson.
 -He based his investigations in Rutherford investigations of the nucleus and helped creating a new and more detailed diagram of the atom.
 -This drawing included the number of each particle an atom had.
 -The model suggested there were layers that surrounded the nucleus where the electrons orbit.
 -Won a Nobel Prize for his atomic model
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  -Developed his ideas in 1926
 -Born August 12, 1887
 -Died January 4, 1961
 -Based his studies in the atomic model of Niels Bohr
 -Stated that the possible positions of electrons could not be determined by the quantum mechanical model of the atom that could predict the odds of the location of an electron
 -His model describes a cloud that covers electrons and according to him the places the cloud was denser there is greater probabilities of finding an electron, while in less denser areas there wasn´t
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  -Developed the theory in 1932
 -Born 20 of October of 1891.
 -Died 24 of July of 1974
 -Discovered the neutrons had the same mass of protons.
 -Also that the neutrons balanced the protons in the nucleus.
 -According to his model electrons that orbited the nucleus were positioned according to the amount of energy they had.
 -Discovered that neutrons could be use to create the atomic bomb.
 -Won Nobel Prize in physics.