DEVELOPMENT OF THE ATOMIC THEORY Part A: HISTORY * 1869: Mendeleev formulated the Table of the Elements - listing them by their atomic weight and grouping them with similar characteristics. * 1897: JJ Thomson discovered electron and isotopes‚ and invented the mass spectrometer. * 1898: Marie Curie discovered and isolated radium‚ a new element which unprompted disintegrated into other elements. This proved that the atoms of one element at least were not indivisible. * 1911: Ernest
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The History of Atomic Theory Atomos: Not to Be Cut The atomic model has changed throughout the centuries starting in 400 BC‚ when it looked like a billiard ball. Democritus: 400 BC The question: Can matter be divided into smaller particles? Or can it be infinitely divided? Matter can be divided into the smallest piece‚he named it “atomos”: not to be cut. Said that atoms were small‚ hard particles that were all made of the same material but were different shapes and sizes. Atoms were
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Atomic theory is the idea that matter is made up of small particles made of atoms. The atomic theory first had 5 points which were stated by John Dalton who came up with it. The first one was that all elements were made up of small units called atoms. The second one was that all atoms of a given element are identical to each other. Third‚ all the atoms were different from all the other atoms. Fourth‚ atoms of different elements combined together in equal numbers to form compounds. Fifth and final
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Democritus Democritus ( 460 a.c.– 370 a.c.) was an Ancient Greek philosopher born in Abdera‚ Thrace‚ Greece. He was an influential pre-Socratic philosopher and pupil of Leucippus‚ who formulated an atomic theory for the universe. His early deductions about the composition of the basic component of nature led him to believe in unseen and uncuttable particles ‚ called atomos. This Greek philosopher wondered how he could be sitting in one part of his house
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The Development of the Atomic Theory Have you ever wondered how the atomic theory came to be? Or have you have wondered who it was that helped in its development? There was not just one man who came up with the atomic theory‚ but there were many scientists that contributed to its development. One of these scientists was Democritus‚ a Greek philosopher. Democritus was the son of Hegesistratus‚ and he was a student of Magians and Chaldaeans. By some authorities he was thought of as the greatest
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The Evolution of the Atomic Theory Rob Congrove B4 10/23/00 The five atomic theorys of the past two centuries represent the sudden advancement of science in modern times. Beginning with a basic theory on the behavior of atoms to the current model‚ some changes have been made‚ and some ideas are still the same. Ancient Greek philosophers believed that everything was made up of invisible particles called atmos. Since then the theory of atoms did not progress until 1803. John
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Dalton was the first scientist to help contribute to the atomic theory. He based his thought process off of Democritus‚ an ancient Greek philosopher‚ who stated that at one point you will not be able to break down matter anymore‚ he called this basic building block an atom (meaning not divisible). Democritus believed that everything around us such as metal‚ water‚ and wood were atoms‚ but Dalton believed and proved that it could be more basic than that. He started thinking of compounds such as water
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and philosophers hundreds even thousands of years to come up with an accurate atomic theory. For nearly 2‚000 years science was unable to come up with experiments that were able to test and put forth the theories made up by Democritus which was a fifth century B.C. Greek philosopher. In 1803‚ John Dalton‚ who viewed the atom as a small solid sphere‚ and is credited for the developing of the first coherent atomic theory was now in the picture. This all led to the the first periodic table of the elements
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Thomson discovered the electron. He continued studying the atomic theory to come up with an improved atomic theory and “The Raisin Bun Theory.” Thomson’s atomic theory was that “matter is composed of atoms that contain electrons (negative particles) embedded in a positive material. The kind of element is characterized by the number of electrons in the atom.” Dalton is known as the one who developed the atomic theory and although some of his theories are proved false today‚ his “pioneer work” helped many
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Research Paper - The Alchemist (Alchemy‚ Magical Realism‚ Gypsies‚ and Fate) Ryan Yoder‚ Ariana Amador‚ Cassie Garza‚ Edgar Vargas R. Medina AP English Lang. & Comp. January 26‚ 2011 Research Paper - The Alchemist (Alchemy‚ Magical Realism‚ Gypsies‚ and Fate) The Alchemist was a book full of many meanings jumbled into one complete novel. For the most part the novel was circled around the point of defining the fate of Santiago’s life. In order to establish the fate of Santiago’s
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