The Development of the Quantum Theory of the Atom

The Development of the Quantum Theory of the Atom

The early beginnings of the quantum theory of the atom start with Niels Bohr, a German physicist. Many problems existed with the theories of the atom at his time, but many resources also existed for deriving more improved models. History previous to this needs to be covered in order to show how the Bohr model began and led to better models

J.J. Thomson proposed that an atom consist of protons and electrons in a sort of “pudding.” However, Ernest Rutherford showed that a beam of positively charged alpha-radiation could be scattered by thin gold foil which showed that an atom is mostly empty space with a small positively charged nucleus to deflect alpha-particles. Thus Rutherford proposed that the electrons orbited the nucleus (but did not fall into it) like planets.1a

The line emission (and absorption) spectra of gases were also another important area of research that would prove useful to explaining the nature of the atom. Johannes Rydberg had found an equation to explain the line spectra of Hydrogen by developing the Rydberg Equation. Though this model had no theoretical basis it would still prove useful.1b

One last piece of information was necessary. The idea of the quantization of energy was proposed by Max Planck to explain black body radiation. However,