Search results
Results From The WOW.Com Content Network
In atomic physics, the Bohr model or Rutherford–Bohr model was the first successful model of the atom. Developed from 1911 to 1918 by Niels Bohr and building on Ernest Rutherford 's nuclear model , it supplanted the plum pudding model of J J Thomson only to be replaced by the quantum atomic model in the 1920s.
Fluorine is a chemical element; it has symbol F and atomic number 9. It is the lightest halogen [ note 1 ] and exists at standard conditions as pale yellow diatomic gas. Fluorine is extremely reactive as it reacts with all other elements except for the light inert gases .
The fluorine compounds decompose into products including fluoride ions. Fluoride is the most bioavailable form of fluorine, and as such, tea is potentially a vehicle for fluoride dosing. [ 29 ] Approximately, 50% of absorbed fluoride is excreted renally with a twenty-four-hour period.
Electron atomic and molecular orbitals A Bohr diagram of lithium. In atomic physics and quantum chemistry, the electron configuration is the distribution of electrons of an atom or molecule (or other physical structure) in atomic or molecular orbitals. [1]
During this period Bohr was working with Walther Kossel, whose papers in 1914 and in 1916 called the orbits "shells". [5] [6] Sommerfeld retained Bohr's planetary model, but added mildly elliptical orbits (characterized by additional quantum numbers ℓ and m) to explain the fine spectroscopic structure of some elements. [7]
Hydrogen fluoride does not boil until 20 °C in contrast to the heavier hydrogen halides, which boil between −85 °C (−120 °F) and −35 °C (−30 °F). [ 6 ] [ 7 ] [ 8 ] This hydrogen bonding between HF molecules gives rise to high viscosity in the liquid phase and lower than expected pressure in the gas phase.
Its structure is analogous to that of sodium chloride, but it is much less soluble in water. It is mainly used as a component of molten salts . [ 4 ] Partly because Li and F are both light elements, and partly because F 2 is highly reactive, formation of LiF from the elements releases one of the highest energies per mass of reactants , second ...
After Bohr's use of Einstein's explanation of the photoelectric effect to relate energy levels in atoms with the wavelength of emitted light, the connection between the structure of electrons in atoms and the emission and absorption spectra of atoms became an increasingly useful tool in the understanding of electrons in atoms. The most ...