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460
460 - 370 B.C , Democritus
Democritus was a Greek philosopher who came up with an idea that atoms are invisible and indestructible particles called atomos which is a greek word that means indivisible. Democritus's idea was rejected because he didn't have the equipment to prove it. https://www.youtube.com/watch?v=TgWn91ap99A -
1766 - 1844 , John Dalton
John Dalton was an English chemist who came up with ideas that formed The Atomic Theory Of Matter . He discovered that elements are made of atoms and compounds are made of different elements.
https://www.youtube.com/watch?v=kJ-6Qy05u_Q -
Late 1800's, J. J. Thompson
J.J. Thompson was an English scientist who discovered the electron. While he was experimenting with a gas discharge tube ,he saw movement in the tube. The movement was called cathode rays which are made of electrons. https://www.youtube.com/watch?v=RW_zfKOU9uM -
Early 1900's Niels Bohr
Niels Bohr was a Danish physicist.Bohr brought up the idea that a model of an atom is similar to a model of the solar system.Bohr discovered that there were energy levels that are a certain distance away from the nucleus which held a certain number of electrons.
https://www.youtube.com/watch?v=Ic8OnvRonb0 -
1871 - 1937 Lord Ernest Rutherford
Rutherford conducted a famous experiment called The Gold Foil Experiment , which consisted of a sheet of gold foil and special equipment.He discovered that atoms are made up of mostly space and that atoms have a small positive nucleus.
https://www.youtube.com/watch?v=zUtIrO3fUgg
