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Period: 370 to 400
Democritus
Democritos was born in Abdera,Greece.He study natural philosophy and published over 70 books.He was adopted and was born to a family of wealth. He had a hypothesis that atoms were irdestructable. Democritus unfortunately died at the age of 90. -
400
democritos
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400
Aristole
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John Dalton
Dalton thought that all mater is made up of tiny microscopes particles calles atoms. The atoms of the same element are identical,those of diffrent particles are diffrent looking. Atoms of diffrent elements combine in small whole numbers ratios to form compounds. -
J.J. Thomson
J.J. Thomson disocvered the electron and he conducted the Cathode Ray Tube experiment.. In the Cathode Ray Tube J.J. thought that by adding a positive charge the moving peices were negetive opisistes. J.J. also founf the Plum pudding model. The Plum pudding model displays electrons embedded in a sphere of positive material. -
Robert Millikan
Robert determined the amount and the charge of the electron. He also conducted the Oil Drop Experiment. He conducted thhis expeirment by measuring the effect of an electric feild on very small oil droplets. -
Ernest Rutherford
Rutherford discovered the nucleous. He did many expeirments like The Gold Foil Expeirment,THe Gold Fold Expeirment, and he also tested the Rutherford model.He thought that for the Gold Foil Expeirment the nucleous is made up of mostly positive charge. -
Neils Bohr
Neils proposed that an electron found only in specific circular paths, or orbit,around the nucleous. In Borhs Model lhe reffered to planetary model because electron move around the nuclous like planets aroumnd the sun. -
Sir James Chadwick
Chadwick confirmed that the existence of nuetrons in the nucleous. He said that the atom is mostly emty space. The atoms consist of two regions, the electron and the cloud.