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   Born: 460 BCE Born: 460 BCE
 Died: 370 BCE
 Year of Discovery: 400 BCE. Naming the atom, created theories about particles.
 Summary: Democritus believed the atoms were unbreakable into smaller parts, suggested all matter was formed of different properties of this particle, and determined the properties of matter.
 Fact: He published over 70 books in his lifetime.
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   Year of Discovery: 400 BCE. Naming the atom, created theories about particles. Year of Discovery: 400 BCE. Naming the atom, created theories about particles.
 Summary: Democritus believed the atoms were unbreakable into smaller parts, suggested all matter was formed of different properties of this particle, and determined the properties of matter.
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   Year of Discovery: 1803 Year of Discovery: 1803
 Summary: Studies led to a conclusion that gases had to be created out of small particles. He created a new atomic theory, saying that matter is made of small, invisible parts that are not capable of being changed or destroyed. Dalton said that each element had a different atom.
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   Born: September 6, 1776 Born: September 6, 1776
 Died: June 27, 1844
 Year of Discovery: 1803
 Summary: Studies led to a conclusion that gases had to be created out of small particles. He created a new atomic theory, saying that matter is made of small, invisible parts that are not capable of being changed or destroyed. Dalton said that each element had a different atom.
 Fact: In his later years, Dalton put the scientific research on hold and focused on teaching.
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   Year of Discovery: 1897 Year of Discovery: 1897
 Summary: Created experiments designed to study the nature of electric discharge within a high-vacuum cathode-ray tube, an area being investigated by many other scientists at the time.
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   Born: December 18, 1856 Born: December 18, 1856
 Died: August 30, 1940
 Year of Discovery: 1897
 Summary: Created experiments designed to study the nature of electric discharge within a high-vacuum cathode-ray tube, an area being investigated by many other scientists at the time.
 Fact: JJ Thomson earned a knighthood in 1908.
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   Born: March 22, 1868 Born: March 22, 1868
 Died: December 19, 1953
 Year of Discovery: 1909
 Summary: He designed the "oil drop experiment" to measure elementary charge. Milikan also wanted to know how to quantify the change of an electron.
 Fact: He was the first person to graduate with a Ph. D. in physics in Columbia.
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  Year of Discovery: 1909
 Summary: He designed the "oil drop experiment" to measure elementary charge. Milikan also wanted to know how to quantify the change of an electron.
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   Year of Discovery: 1911, discovered the nucleus Year of Discovery: 1911, discovered the nucleus
 Summary: Rutherford discovered the nucleus using the gold foil experiment.
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   Born: August 30, 1871 Born: August 30, 1871
 Died: October 19, 1937
 Year of Discovery: 1911, discovered the nucleus
 Summary: Rutherford discovered the nucleus using the gold foil experiment.
 Fact: He was the fourth of twelve children
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   Born: October 7, 1885 Born: October 7, 1885
 Died: November 18, 1962
 Year of Discovery: 1913
 Summary: Proposed a theory for the hydrogen atom, based off the quantum theory, where some physical quantities take only discrete values. Bohr discovered that electrons move around the nucleus, only in prescribed orbits. Also, he discovered that if electrons maneuver to a lower-energy orbit, the difference is sent out as radiation.
 Fact: He was president of the Royal Danish Academy of Sciences.
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   Year of Discovery: 1913 Year of Discovery: 1913
 Summary: Proposed a theory for the hydrogen atom, based off the quantum theory, where some physical quantities take only discrete values. Bohr discovered that electrons move around the nucleus, only in prescribed orbits. Also, he discovered that if electrons maneuver to a lower-energy orbit, the difference is sent out as radiation.
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   Born: December 5, 1901 Born: December 5, 1901
 Died: February 1, 1976
 Year of Discovery: 1925
 Summary: Heisenberg believed that Niels Bohr's previous theory gave a good description of the spectrum made by the hydrogen atom, but this needed to be developed to suit more complicated atoms and molecules. In 1925, Werner formulated a type of quantum mechanics based on matrices.
 Fact: He won a Noble Proze in Physics in 1932.
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   Year of Discovery: 1925 Year of Discovery: 1925
 Summary: Heisenberg believed that Niels Bohr's previous theory gave a good description of the spectrum made by the hydrogen atom, but this needed to be developed to suit more complicated atoms and molecules. In 1925, Werner formulated a type of quantum mechanics based on matrices.
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   Born: August 12, 1887 Born: August 12, 1887
 Died: January 4, 1961
 Year of Discovery: 1926
 Summary: Erwin is known for, his greatest discovery, the Schrodinger's Wave Equation. This equation is a result from his dissatisfaction with the quantum condition in Bohr's orbit theory and his beliefs that the atomic spectra should be determined by a certain type of eigenvalue problem.
 Fact: After Erwin finished his chemistry studies, he devoted himself, for many years, to Italian painting.
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   Year of Discovery: 1926 Year of Discovery: 1926
 Summary: Erwin is known for, his greatest discovery, the Schrodinger's Wave Equation. This equation is a result from his dissatisfaction with the quantum condition in Bohr's orbit theory and his beliefs that the atomic spectra should be determined by a certain type of eigenvalue problem.
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   Year of Discovery: 1932 Year of Discovery: 1932
 Summary: Chadwick made a fundamental discovery in the domain of nuclear science. With this discovery, he proved the existence of neutrons. With a new tool in atomic disintegration, need not overcome electrical barrier, allows it to be capable of penetrating and splitting the nuclei of the heaviest elements; paving the way towards fission of uranium 235 and the creation of atomic bombs.
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   Born: October 20, 1891 Born: October 20, 1891
 Died: July 24, 1974
 Year of Discovery: 1932
 Summary: Chadwick made a fundamental discovery in the domain of nuclear science. With this discovery, he proved the existence of neutrons. With a new tool in atomic disintegration, need not overcome electrical barrier, allows it to be capable of penetrating and splitting the nuclei of the heaviest elements; paving the way towards fission of uranium 235 and the creation of atomic bombs.
 Fact: Sir James was knighted in 1945