feb 8, 1904 - Thomson’s Model of the Atom

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The model that was made from Thomson's theory is known as the "raisin bun" or "plum pudding" model. Thomson’s experiments with a Crook’s tube, while he was learning and building the passage of an electric current through a gas, later led to his discovery of very light negative particles called electrons. This proved that
Dalton’s theory that the atom was indivisible was false. Thomson’s later experiments with gas discharge tubes led to the discovery of much heavier positive particles that were much later identified as protons. Thomson believed that all electrons have small masses and a negative charge, also that an atom is a sphere of positive electricity. finally he concluded that negative electrons are planted inside of the positive sphere, so that the other atom left is uncharged.

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