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Democritus Model
It was the most simple of the models, pretty much he believed that there were atoms, only they were small indivisible spheres, with no internal structure, or nucleus, or charge, but it was just a theory that wasn't scientifically proven. -
Dalton's Model
His atomic theory said that elements consisted of tiny particles called atoms. It states an element is one of a kind because all atoms of an element are identical. All the atoms that make up the element have the same mass. All elements are different from each other due to differing masses. -
When were elcetrons discovered
Founded by J.J. Thomas and his colleagues. -
Thomson's Model
An English physicist Joesph John Thomas inffered from his experiments that atoms contained small, negatively charged particles. Thomas thought these electrons were evenly embedded throughout a positively charged sphere. -
Rutherford's Model
A British physicist, Ernest Rutherford, proposed that almost all the mass of an atom and all its positive charges were concentrated in a central atomic nucleus surrounded by electrons. -
Bohr's Model
A Danish physicist Niels Bohr hypothesized that electrons traveled in a fixed orbits around the atom's nucleus. Then a student of Bohr, James Chadwick, concluded that the nucleus contained positive and neutral neutrons. -
The discovery of the proton
Discovered by Rutherford and some of partners. -
Electron Cloud Model
According to the currently used model of atomic structure, electrons do not follow fixed orbits but tend to occur more frequently in certain areas around thr nucleus at any given time. -
The discovery of the Neutron
Discovered by James Chadwick
