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Rutherford equation

Gaussian distribution, discussion and equation, 61,269-274 of Rutherford and Geiger radioactivity data, 274, 275... [Pg.346]

According to the Dirac equation the 2Sm and 2P1/2 states coincide. It was, however, observed by Lamb and Rutherford that the 2level shift, one must take into account the quantum aspect of the electromagnetic field as well as those of the negaton-positon field. [Pg.641]

Using the new nomenclature, the nuclear reaction that led to Rutherfords discovery of the proton can be written as an equation ... [Pg.35]

This equation says that a nitrogen nucleus is composed of seven protons and seven neutrons. An alpha particle, which is identical to a helium ion, has two protons and two neutrons. A highly energetic collision fuses the two nuclei. The result is a rare isotope of oxygen with eight protons and nine neutrons. The leftover proton is ejected. And that proton is what Rutherford detected. [Pg.36]

The discovery of two new elements started a frenetic race to find more. Actinium was soon unearthed (Debierne 1900) and many other substances were isolated from U and Th which also seemed to be new elements. One of these was discovered somewhat fortuitously. Several workers had noticed that the radioactivity of Th salts seemed to vary randomly with time and they noticed that the variation correlated with drafts in the lab, appearing to reflect a radioactive emanation which could be blown away from the surface of the Th. This Th-emanation was not attracted by charge and appeared to be a gas, °Rn, as it turns out, although Rutherford at first speculated that it was Th vapor. Rutherford swept some of the Th-emanation into a jar and repeatedly measured its ability to ionize air in order to assess its radioactivity. He was therefore the first to report an exponential decrease in radioactivity with time, and his 1900 paper on the subject introduced the familiar equation dN/dt = - iN, as well as the concept of half-lives (Rutherford 1900a). His measured half-life for the Th emanation of 60 seconds was remarkably close to our present assessment of 55.6 seconds for °Rn. [Pg.663]

If the force between the beam particle and the target nucleus is assumed to be the Coulomb force, the basic equation for the differential scattering cross-section is given by Rutherford s formula ... [Pg.89]

Equation (2.2) is just the Rutherford cross section for scattering of, strictly speaking, free charges. To apply this to atomic electrons that are not free but can be excited4 with energy En, Bohr surmised the sum rule... [Pg.13]

There have been several brave attempts to evaluate generalized oscillator strengths which involve matrix elements of the type of equation (15). Such computations are quite laborious [62] because of numerous high-lying states involved, and much computation time is employed to confirm the validity of Rutherford s law although that may not be evident. More seriously, such calculations can at best serve a complete evaluation of a stopping cross section in... [Pg.106]

A program to solve these equations has been described by Orlov et al. (1998). O Keeffe (1989) has described an alternative method that is suitable for performing the calculation by hand. Rutherford (1990) has presented a way of inverting the matrix that retains the symmetry of the equations by including all Aa of the equations of type 3.3. Brown (1977) has described a robust iterative technique for solving the equations based on recognizing that eqn (3.4) is an expression of the principle of maximum symmetry (Rule 3.1). In this procedure... [Pg.240]

One problem with the network equations is that they can, on occasion, give rise to negative bond valences which have no physical significance (expect to indicate that, from a chemical point of view, the bond should not exist). Rutherford (1998) has explored the resonance bond model as an alternative to the use of the loop equation (Section 14.4) while Rao and Brown (1998) have suggested using the method of maximum entropy (Section 11.2.2.1). [Pg.243]

Rutherford [43] reports the use of the modified Rackett equation to correlate the density for alkyl chlorides (1-chloroethane, 1-chloropropane, and 1-chlorobutane) and bromides (bromomethane, bromoethane, and bromopropane) as a function of temperature, pressure, and critical point data. [Pg.49]

CHEMICAL ENGINEERING SYSTEMS BY THE FABRICATION, SOLUTION, AND PRESENTATION OF ORDINARY AND PARTIAL DIFFERENTIAL EQUATIONS COPIOUSLY ILLUSTRATED BY EXAMPLES FROM THE PAPERS OF RUTHERFORD ARIS... [Pg.498]

QM grew out of studies of blackbody radiation and of the photoelectric effect. Besides QM, radioactivity and relativity contributed to the transition from classical to modem physics. The classical Rutherford nuclear atom, the Bohr atom, and the Schrodinger wave-mechanical atom are discussed. Hybridization, wavefunctions, Slater determinants and other basic concepts are explained. For obtaining eigenvectors and eigenvalues from the secular equations the elegant and simple matrix diagonalization method is explained and used. All the necessary mathematics is explained. [Pg.85]

By now, it was becoming clear that there was a connection between electrons in bodies, the radiant energy emitted by those bodies, and the distribution of that energy in the spectrum. But a more detailed theory with more information was needed. Rutherford had proposed an atom modeled on the solar system, with electrons orbiting around a positive nucleus and a lot of empty space between the electrons and the nucleus. In 1913 the Danish physicist Niels Bohr (1885-1962), who worked with Rutherford for four years and on his return to Copenhagen made Denmark a world center of theoretical physics, published one of the twentieth century s most important papers. He applied Planck s equation and the notion of quantization of energy to Rutherford s... [Pg.176]

The mathematical treatment of the Rutherford-Bohr atom was especially productive in Denmark and Germany. It led directly to quantum mechanics, which treated electrons as particles. Electrons, however, like light, were part of electromagnetic radiation, and radiation was generally understood to be a wave phenomenon. In 1924, the French physicist Prince Louis de Broglie (1892-1987), influenced by Einstein s work on the photoelectric effect, showed that electrons had both wave and particle aspects. Wave mechanics, an alternative approach to quantum physics, was soon developed, based on the wave equation formulated in 1926 by the Austrian-born Erwin Schrodinger (1887-1961). Quantum mechanics and wave mechanics turned out to be complementary and both were fruitful for an understanding of valence. [Pg.177]

The first term of (6.85) is the T-matrix element for elastic scattering by the potential U. If U is the Coulomb potential Vc it is the Rutherford-scattering T-matrix element. The second term is the distorted-wave T-matrix element for which we solve the distorted-wave Lippmann-Schwinger equation formed from (6.81). Its explicit form is written by expanding in the complete set of eigenstates of K -I-17. This may include projectile bound states A) defined by... [Pg.153]

This chapter has been reorganized to place greater emphasis on the physical structure of the atom, as determined from the classic experiments of Thomson, Millikan, and Rutherford. The chapter ends with direct scanning tunneling microscopy images of individual atoms in chemical reactions. Section 1.6 in Principles of Modern Chemistry, fifth edition (mole, density, molecular volume), has been moved to Chapter 2, which now gives a comprehensive treatment of formulas, stoichiometry, and chemical equations. [Pg.1082]

The first nuclear transformation (discovered by Rutherford) can be represented by the shorthand notation yN (a, p) IgO. (a) Write the corresponding nuclear equation... [Pg.1037]

According to conventional theory, the equation Rexp = Rconv should also be valid for ECS. However, the cross section for electron scattering from hydrogen, carbon and oxygen is simply the Rutherford cross section ax oc Z (Zx atomic number of atom X). Calculations of the cross section based on the electronic structure show that screening effects are not important under these conditions [Vos 2002 (a) Chatzidimitriou-Dreismann 2003 (a)]. The results reveal that, as in the case of NCS, the measured ratio ReXp of the hydrogen peak and the joint oxygen / carbon peak is considerably decreased Rexp < Rconv-... [Pg.496]


See other pages where Rutherford equation is mentioned: [Pg.46]    [Pg.46]    [Pg.384]    [Pg.54]    [Pg.54]    [Pg.610]    [Pg.46]    [Pg.46]    [Pg.384]    [Pg.54]    [Pg.54]    [Pg.610]    [Pg.481]    [Pg.82]    [Pg.371]    [Pg.50]    [Pg.183]    [Pg.114]    [Pg.25]    [Pg.94]    [Pg.102]    [Pg.262]    [Pg.177]    [Pg.948]    [Pg.215]    [Pg.97]    [Pg.2]    [Pg.127]    [Pg.150]   
See also in sourсe #XX -- [ Pg.384 ]

See also in sourсe #XX -- [ Pg.610 ]




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