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Idea of the Atom
It was discovered by Democritus In 440 BC but the website won't let me set it to 440 BC -
Daltons atomic theory
Dalton theory on the Atom -
Discovery of Electrons
Experiments by J.J. Thomson in 1897 led to the discovery of a fundamental building block of matter -
Discovery of the nucleus in an Atom
The nucleus is the very dense region consisting of protons and neutrons at the center of an atom. Discovered by Ernest Rutherford -
Discovery of Protons
Shortly after the World War I, in 1920, Rutherford proposed the name proton for the positively charged particles in the nucleus of an atom -
Electron orbitals, shells and clouds
Niels Bohr described atomic structure and the presence of orbital shells. The atomic model consisted of successive shells, in which the electrons were arranged -
Discovery of Neutrons
It is remarkable that the neutron was not discovered until 1932 when James Chadwick used scattering data to calculate the mass of this neutral particle
