Bohr model (Wikipedia)
In atomic physics, the Bohr model or Rutherford–Bohr model is an obsolete model of the atom, presented by Niels Bohr and Ernest Rutherford in 1913. It consists of a small, dense nucleus surrounded by orbiting electrons. It is analogous to the structure of the Solar System, but with attraction provided by electrostatic force rather than gravity, and with the electron energies quantized (assuming only discrete values).- The Rutherford model was devised by Ernest Rutherford to describe an atom. Rutherford directed the Geiger–Marsden experiment in 1909, which suggested, upon Rutherford’s 1911 analysis, that J. J. Thomson’s plum pudding model of the atom was incorrect. Rutherford’s new model for the atom, based on the experimental results, contained new features of a relatively high central charge concentrated into a very small volume in comparison to the rest of the atom and with this central volume containing most of the atom’s mass; this region would be known as the atomic nucleus. The Rutherford model was subsequently superseded by the Bohr model.
- Tertiary (Wikipedia)
Tertiary (/ˈtɜːr.ʃə.ri, ˈtɜːr.ʃiˌɛr.i/ TUR-shə-ree, TUR-shee-err-ee) is an obsolete term for the geologic period from 66 million to 2.6 million years ago. The period began with the demise of the non-avian dinosaurs in the Cretaceous–Paleogene extinction event, at the start of the Cenozoic Era, and extended to the beginning of the Quaternary glaciation at the end of the Pliocene Epoch. The time span covered by the Tertiary has no exact equivalent in the current geologic time system, but it is essentially the merged Paleogene and Neogene periods, which are informally called the Early Tertiary and the Late Tertiary, respectively.