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400 BCE
Democritus
Democritus was basically saying the opposite of what Aristotle said he said that there has to be an end eventually. -
384 BCE
Aristotle
Aristotle said that anything can be divided infinitely even atoms. -
John Dalton
a short summary of what John Dalton is that he discovered that atoms are the smallest of things they can not be broken down any farther. -
William Conrad Roentgen
William Conrad Röntgen discovered the X-Ray. -
J.J. Thomson
JJ Thomson discovered a new model and called it "Plum Pudding" if you've never had plum pudding o never herd of this before let me clear things up. he discovered that electrons cant just be there because there negative and you need a positive substance to balance it out so he thought that the electrons were in a bunch of positive substance like plums in plum pudding. -
Hantaro Nagaoka
he made a proposal of the first model with a small nucleus surrounded with a with a ring of electrons. -
Ernest Marsden
Ernest Marsden discovered the nucleus from Rutherfords experiment or using the Gold Foil experiment. -
Ernest Rutherford
Ernest Rutherford discovered the nucleus and that the atom is mostly empty space. -
Niels Bohr
Niels Bohr discovered the shells because he knew something was wrong about the atom because the electrons would have sunk into the nucleus. -
Henry Moseley
he provided the first experimental evidence of Niels Bohr.