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Period: to
The Atom
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1808 Dalton Model
John Dalton a brittish chemist concluded that every element is made up of atoms. he also thought that different elements have different atoms of different weights. Dalton pictured atoms as tiny solid balls -
1897 Thomson Model
As well as John Dalton the scientist J.J. Thomson was also a brittish scientist. Thomson discovered the electron. He proposed that the atom is a positivley charged sphere with electrons embeded in it, he compared it to a muffin with raisins embedded into it with the muffin being the atom and the raisins being the electrons -
1904 Nagaoka Model
Hantro Nagaoka a japanese physicist proposed that an atom is a large sphere in the center with a positive charge with the electrons revolving around it. just like planets around the sun. -
1911 Ruthford Model
A Brittish physicist Ernest Ruthford concluded that the atom is mostly empty space. he also concluded that elctrons orbit randomly around the positivley charged Nucleus. -
1913 Boher Model
a danish Physicist Niels Boher proposed a model that showed electrons orbiting on specific layers. he said that atoms absorb or give off energy when the electrons move, -
2000 The present Model
the present model conculdes that electrons are negativly charged cloud around the nucleus. it is immpossible to determine exactly where an electron is at any given time.
