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Democritus had an idea of atoms but in a void. Democritus Atomic theory explains the existence of atoms and also its features.
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Dalton believed that:
1. All matter is composed of atoms
2. Atoms cannot be made or destroyed
3. All atoms of the same element are identical
4. Different elements have different types of atoms
5. Chemical reactions occur when atoms are rearranged
6. Compounds are formed from atoms of the constituent elements -
Michael Faraday verified that electrical force helped together an atom.
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Julius Plucker built one of the first gas discharge tubes also known as a Cathode ray tube.
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He developed the Crookes tube and in it produced cathode rays for the first time. He also invented the radiometer and spinthariscope.
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William discovered X-rays while using the cathode ray tube. He found that X-rays can travel through solid objects.
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A french physicist who found that rays coming from a uranium ore affected a photographic plate like X-rays did. The rays were not from an external source and were more powerful than those from a sample of pure uranium. His experiment led to the discovery of natural radiocativity.
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He discovered the Plum pudding model of the atom and he describes the atom as a slightly positive sphere with small electrons inside.
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He discovered a plantery model of the atom based on saturns rigs but this moel was incorrect.
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Discovered the charge of an electron with his oil drop experiment.
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Rutherford theorized that atoms have a small positive chard in a small nucleus. He tested this theory with the gold foil experiment and he came up with a new model.
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He believed that outer orbitals could hold more electrons than inner orbitals. He also suggested that the outer orbitals determine the atom's chemical property.
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Electrons do not have fixed orbitals but have quantum mechanical orbitals. They float in the orbitals and each orbital has a certain amount of energy.
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They built an accelerator and bombarded lithium with protons to make alpha particles.
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Saw electons as a continuous clouds and introduced wave mechanics as a mathmatical model of an atom.
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He did the first controlled chain reaction releasing energy from the atom's nucleus.
