Niels+Bohr+Hall

 Niels Bohr  October 7, 1885  Professor of Physiology at Copenhagen University  Niels Bohr’s research took place in 1913.  Niels Bohr’s research took place in Manchester, England.

Bohr attended Copenhagen University in Denmark for eight years and received a doctorate degree; he also worked at Cavendish Laboratory at Cambridge. It wasn’t until he went to Manchester in 1913 when he took over the Rutherford’s atom theory and refined it. He then began to build an atomic model which was an improvement of Rutherford’s model that helped him demonstrate his atomic theory.

1. Electrons only orbit around certain parts around the nucleus; these orbits are called stationary orbits. 2. Each orbit has an energy that goes with it such as E1, then E2 starting closest to the nucleus and moving farther away. 3. Light is absorbed when it jumps form a lower to a higher orbit and emitted when an electron jumps from a higher orbit to a lower orbit. 4. The difference between the two orbit energies is given by the energy and frequency of light either emitted or absorbed.
 * The Bohr model consists of four principles: **



E(light) = Ef - Ei   n  = E(light)/h h= Planck's constant = 6.627x10-34 Js    where "f" and "i" represent final and initial orbits.

** Main **** points of his theory ** 1. Electrons can only occupy certain orbits or shells in an atom. Each orbit represents a definite energy for the electrons in it. 2. Light is emitted by an atom when an electron jumps from one of its allowed orbits to another. Since each orbit represents definite electron energy, this electron jump, or transition, represents definite energy jump. This change in electron energy leads to emission of light of a definite energy or wavelength.

Niels Bohr used Thomas and Rutherford’s atomic model to do his research and to improve upon their ideas and make it his own. ** Bohr took Rutherford’s idea of the atomic model and added the idea of fixed orbits or having energy for the electron traveling around the nucleus. This model showed that electrons can get energized and move to higher energy levels for a short amount of time. **

Bohr's theory and construction of his look on the atomic structure was developed by the incorporation of information from Rutherford's ideas of the atom as well as Planck's Quantum Theory.