Bohr, Neils

Bohr, Neils (Denmark) in 1913 proposed an atomic model where electrons could move only in certain stable orbits. He won the Nobel Prize in Physics in 1922 and died in 1962 at age 77. 

W. Pauli, Neils Bohr and the Development of Physics, McGraw-Hill, New York, 1955. 

C.H. Langford, Concordia University Dr. Wrighton s paper maintains appropriate discretion with respect to the twenty-first century. As Neils Bohr said, "Prediction is difficult, especially about the future". However, he does call attention to a number of problems in solid state and interfacial chemistry which are certainly important now and would not have been likely to be picked out for emphasis in a meeting of inorganic chemists held ten years ago and oriented to the theme of... 

The structure of the atom as drawn here, with electrons orbiting a central positive nucleus, was proposed by the Danish scientist, Neils Bohr. It worked well for hydrogen, but is not a good model for the atoms of other elements. 

Neils Bohr (1885-1962) proposed an orbital model of the nuclear atom in which electrons in an atom moved around the nucleus, just as planets move around the sun. 

The extraordinary minds of Albert Einstein, Neils Bohr, Marie Curie, Enrico Fermi, and countless others provided the insight, experimentation, and sheer brain power needed to illuminate the nature of the atom. Their legacy provides a spectacular foundation for the future unraveling of atomic mysteries. 

Neils Bohr Planetary model of electrons Developed the idea of distinct energy levels where electrons could be found— similar to planets in the solar system... 

It was the analysis of the line spectrum of hydrogen observed by J. J. Balmer and others that led Neils Bohr to a treatment of the hydrogen atom that is now referred to as the Bohr model. In that model, there are supposedly allowed orbits in which the electron can move around the nucleus without radiating electromagnetic energy. The orbits are those for which the angular momentum, mvr, can have only certain values (they are referred to as quantized). This condition can be represented by the relationship... 

The element is named after Neils Bohr. The first announced detection of element 107 was at the Joint Institute for Nuclear Research (JINR) in Dubna. Because the experimenters saw the element for only 2/1000th of a second, it was difficult to determine anything about it. The first confirmation of... 

The Cognitive Correspondence Principle Named after the inspiration of Neils Bohr in tying quantum physics to Newtonian physics, this principle recognizes the mathematical hierarchy required in modeling complex systems and need to make simplifying assumptions. It states that each assumption must, in the limit, be found to be a valid truncation of a more precise mathematical description of the overall system. 

Neils Bohr, the quantum mechanical explanation of the atom... 

Electron Orbits. The first attempt to solve the problem of the arrangement of the electrons around the nucleus was made by Sir Ernest Rutherford when he suggested that the electrons revolve round the nucleus like the planets revolve round the sun. Neils Bohr pointed out, however, that the number of orbits available for these electrons must be limited and that the electrons could only rotate in orbits in which they possess definite discrete amounts or quanta of energy thus the only orbits available would be those in which the electrons have one, two, three, four,. . . etc., quanta of energy. 

To solve this contradiction, in 1913, the Danish physicist Neils Bohr (then studying under Rutherford) postulated that the electron orbiting the nucleus could move only in certain orbits, having in each a certain quantized energy. It turns out that the colors in fireworks would help prove him right. 

Figure 3.25 Neils Bohr, who in 1913 postulated the Bohr model of the hydrogen atom, from which derives the notion of electronicshellsthat initiated the modern atomictheory of chemical reactions, as well as the concept of energy levels that underlie the design of lasers. (Published with permission from the Deutsches Museum, Munich.)...

In 1913, Neils Bohr applied quantum theory to atomic structure, using his analysis of the spectral lines in the light emitted hy hydrogen atoms. Bohr explained the frequencies of these spectral lines hy expressing them in terms of the charge and mass of the electron and Planck s constant He postulated that an atom would not emit radiation while in one of its stable states, hut would do so when it made a transition between states. The frequency of the emitted radiation would be equal to the difference in energy between states divided by Planck s constant An atom could not absorb nor emit radiation continuously but could do so only in finite steps called quantum jumps. 

In 1913 AD, Neils Bohr used tire particle theory of the electron to explain the spectrum of the hydrogen atom. 

Pauli, Wolfgang (1900-1958) was bom in Vienna, Austria. He obtained his doctoral degree in 1921 from the University of Munich. After that he worked with Max Born and then with Neils Bohr. He held various appointments in the United States during World War II, including the Institute of Advanced Study in Princeton. After the war he returned to the Federal Institute of Technology in Zurich as Professor of Theoretical Physics. He won the 1945 Nobel Prize in Physics for developing the eponymous exclusion principle. 

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