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Dalton
He believed that the theory of matter consists of invisible particles called atoms and that atoms of a given element are al identical and can neither be created nor destroyed. -
J.J Thomson
He discovered electrons. Then he found out that atoms are made up of a proton, neutron, and electons. He then realized that an atom is not invisible -
Rutherford
He discovered that an atom is made up of a central positive nucleus. The atom is surrounded by electrons that are negatively charged. -
Bohr
His discovery was close to Rutherfords. He discovered that electrons orbit the outside of the nucleus in a circular motion. Electrons also form different shells around the atom. The amount of energy the atom releases is determined by the size of the orbit. -
Chadwick
He discovered neutrons and found that their purpose is to be in the nucleus and only the nucleus with the protons to stabilize the nucleus. He also discovered that neutrons have a neutral charge. -
Modern Day
Different scientists haven't discoved anything else besides that a negative atom is attracted to a positve atom. They are also discovering more elements to add on the periodic table.
