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John Dalton - Matter is made of indivisible parts dependent upon the compound
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J.J. Thomson - The atom is made of positive and negative parts, the positive part holding most of the mass. The negative part is in an integer count of finite amounts of mass. The positive is spread evenly throughout with negative bits dispersed through it like plum pudding.
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Ernest Rutherford - In the gold foil experiment, he determined that since alpha particles were repelled at high angles, the atom must have a small, dense center that holds all of the positive charge. Thomson's Grad Student.
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Niels Bohr - Like Rutherfords model but with fixed energy levels since different elements have specific discrete emission spectra, meaning the electrons can only shift between specific places.
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Erwin Shrödinger - Electrons are standing probability waves with orbitals rather than moving through specific orbits. This is why they are not continuously radiating energy. [https://chem.libretexts.org/Bookshelves/Introductory_Chemistry/Map%3A_Introductory_Chemistry_(Tro)/09%3A_Electrons_in_Atoms_and_the_Periodic_Table/9.06%3A_Quantum-Mechanical_Orbitals_and_Electron_Configurations]
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Our understanding of the quantum model has been furthered, but we have not had a new model for close to 100 years!