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The Bohr model is a relatively primitive model of the hydrogen atom, compared to the valence shell model. As a theory, it can be derived as a first-order approximation of the hydrogen atom using the broader and much more accurate quantum mechanics and thus may be considered to be an obsolete scientific theory .
John William Nicholson is noted as the first to create an atomic model that quantized angular momentum as h/2π. [11] [12] Niels Bohr quoted him in his 1913 paper of the Bohr model of the atom. [13] 1912 – Victor Hess discovers the existence of cosmic radiation.
The Bohr model was developed beginning 1913, and championed the idea of electron configurations that determine chemical properties. Bohr proposed that elements in the same group behaved similarly because they have similar electron configurations, and that noble gases had filled valence shells; [102] this forms the basis of the modern octet rule ...
The model's key success lay in explaining the Rydberg formula for the spectral emission lines of atomic hydrogen by using the transitions of electrons between orbits. [24]: 276 While the Rydberg formula had been known experimentally, it did not gain a theoretical underpinning until the Bohr model was introduced. Not only did the Bohr model ...
Rutherford's model, being supported primarily by scattering data unfamiliar to many scientists, did not catch on until Niels Bohr joined Rutherford's lab and developed a new model for the electrons. [56]: 304 Rutherford model predicted that the scattering of alpha particles would be proportional to the square of the atomic charge.
1911 – Ernest Rutherford: Discovery of the atomic nucleus (Rutherford model) 1911 – Kamerlingh Onnes: Superconductivity; 1912 - Victor Francis Hess: Cosmic rays; 1913 – Niels Bohr: Bohr model of the atom; 1915 – Albert Einstein: General relativity; 1915 – Emmy Noether: Noether's theorem relates symmetries to conservation laws.
Calculations based on the Bohr–Sommerfeld model were able to accurately explain a number of more complex atomic spectral effects. For example, up to first-order perturbations, the Bohr model and quantum mechanics make the same predictions for the spectral line splitting in the Stark effect. At higher-order perturbations, however, the Bohr ...
His proposals were based on the then current Bohr model of the atom, in which the electron shells were orbits at a fixed distance from the nucleus. Bohr's original configurations would seem strange to a present-day chemist: sulfur was given as 2.4.4.6 instead of 1s 2 2s 2 2p 6 3s 2 3p 4 (2.8.6). Bohr used 4 and 6 following Alfred Werner's 1893 ...