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Daltons model
Dalton States that all matter is composed of atoms. It also informs us that atoms cannot be made or destroyed. It continues in saying that all atoms of the same element are identical and experience chemical reactions when atoms are rearranged. The combining of these elements with each other are called compounds and these chemical elements are made of atoms. These atoms only combine in small, whole number ratio such as 1:1, 1:2, 2:3 and so on. -
Dmitri Mendeleev
Dmitri created the first periodic table and left blanks for new discoveries. -
Thomas's model(Plum pudding)
Thomas Suggested that cathode rays consisted of negatively changed rays, even smaller than atoms. He suggested these particles where subatomic parts of the atom. Thomas purposed that the atom was a mass of positive charge with negative electrons placed into it like raisins in pudding. -
Ernest Rutherfords model
1906 Rutherford and his assistants performed the gold foil experiment that led to the atomic nucleus and that atoms are mostly space -
Robert Milikan
Discovered the change of an electron with his oil drop experiment at the university of Chicago. -
Bohrs model
In 1913 Bohr and his partner Danish who was a Physicist suggested applying the Quantum Theory to the Rutherford model. The new model purposed that electrons are in fixed energy levels he called orbits. The energy of these orbits is quantized and electrons must absorb or release photons in order to move from different energy levels. -
Electron cloud
The electron cloud model is a model where the electrons no longer orbit around the nucleus. we shouldn’t know exactly where they are, and hence describe their probable location around the nucleus only as an arbitrary ‘cloud’. -
Geiger
Demonstrated that energy and mass are conserved in atomic processes. -
Chadwick
Discovered the neutron -
Glen Seaborg
Succeeded in making man-made elements.
