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John Dalton published his "New System of Chemical Philosphy." In it he explined that every element is made of atoms and that each element has atoms of different mass.
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J. J. Thomson was a British scientist who thought of a new model. He said that an atom is a positively-charged ball with electrons within it. His model looked like a muffin with berries in it.
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Hantaro Nagaoka was a Japanese physicist that proposed a new model of an atom. His model was a large sphere in the middle with a posotive charge. The electrons were revolving around the sphere like the solar system.
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Ernest Rutherford was a British physicist who believed an atom to be mostly an empty space. Electrons go around randomly around a small positively charged nucteus.
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Niels Bohr was a Danish physicist that said that the electrons in an atom wernt randomly located around a nucleus but moving in specific layers. He stated that electons absorbe or give off energy when they move from one shell to another.
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The current model of the atom was formed with the help of many scientists from the 1920s to today. The current model show the electrons forming a negatively charged cloud around the nucleus. It is impossible to detemine where an electron is at a given time.
