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Athens, Greece He decided matter must be made up of atoms
This was the beginning of atomic theory. -
England Proposed the idea of a mechanical universe with small masses in motion.
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Cumberland, England Printed the first table of relative weights of elements. Invented atomic weight.
First classification of atoms -
Ireland Introduced concept of electrons. Because of this, many things such as valency and conduction can be explained
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England Proposed "plum pudding Model"
It is the basis for the current atomic model -
Kiel, Germany Used the idea of quanta (discrete units of energy) to explain hot glowing matter. This helped us understand more atomic behaviour.
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Nagasaki, Japan Proposed the 'Saturnian model', where an atom is compared to Saturn and its rings
It correctly predicted that electrons orbit the nucleus -
Illinois Discovered the charge and mass of electrons
More of an understanding of atomic behaviour -
Essex, England Proposed the 'Rutherford model' where there is a small positive nucleus and negative electrons orbiting
Scientists realise that atoms are made up of sub-atomic particles -
England Rearranged the Periodic table so it was arranged by atomic number not atomic weight. Made accurate predictions on missing elements
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Copenhagen, Denmark Proposed 'Bohr model' where the electrons are arranged in shells
This is the current atomic model -
England Discovered the neutron