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Proposed that matter is made of small unbreakable particles call atoms.
Atoms are solid. -
Stated that all substances are made of 4 elements.
1. Fire
2. Water
3. Air
4. Earth -
Transformed Democritus' ideas on atoms into a modern atomic model.
All matter is made of tiny microscopic particles called atoms. -
Discovered the electron and conducted the cathode ray tube experiment.
By adding an electric charge he found that the moving pieces were (negative) opposites. -
Determined the mass and chaarge of the electron. Robert conducted oil drop experiment by measuring the effect of an elctric field on very small oil droplets.
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Ernest Rutherford discovered the nucleus. The nucleus is made up of mostly +charge and mass.
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He proposed that an electron is found only in specific circular paths.
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Confirmed the existence of the nuetron in the nucleus.