Chemistry & Physics. Chemistry 301: The Development of the Atomic Theory. Season 1 Episode 301 | 21m 19s. The terms theory and model are defined, and students learn how a theory remains valid.

Rutherford and Bohr describe atomic structure 1913. Photo: Niels Bohr's research notes for his new atomic theory. In 1911, Niels Bohr earned his PhD in Denmark with a dissertation on the electron ...