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425
democritus's model of the atom
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452
Democritus
452 BC
greek scientist who became the first to develope the idea of the atom and a model of it. believed it to be the simplest form of matter. from the greek word 'atomos' meaning indivisible. -
Antoine Lavoisier
conducted the burning log experiment. concluded that elements cannot be broken down and they also react with eachother. created the law of conservation. -
Joseph Proust
Conducted a copper (Cu) oxygen (O) experiment, then developed the law of definate proportions -
John Dalton
created the four postulates. concluded that matter is made of small particles and that there are three forms of atoms: simple' compound, and complex. -
J.J. Thomson
conductd the cathode ray experiment. discovered electrons. and developed a model called the plum pudding model. -
J.J. Thomson
plum pudding electron model -
Robert Millikan
conducted the oil drop experiment and found the mass and voltage of the electron -
Ernest Rutherford
Conducted the gold foil (alpha scattering) experiment. discovered that there is a nucleus in an atom. -
Niels Bohr
conducted the spectro light of atoms experiment. states that the atom is one one then thousandth the size of what other sciemtists predicted it tobe. -
Ernest Rutherford
model of the atom with a nucleuss -
Niels Bohr
his model of the atom