jan 1, 1904 - thomspon model of atom

Description:

refered to as "the raisin bun" or "plum pudding" model.
He proposed - electrons have a small mass and negetive charge, atom is a sphere of positive electricity, negative electrons are embedded in the positive sphere - the resulting atom is neutral or uncharged
His experiments with a Crooks tube while studying the passage of an electric current through a gas led to his discovery of a very light negative particles called electrons. Further experiments with gas discharge tubes would lead to the discovery of much heavier positive particles which later are identified as protons.

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