Beta-minus

Neutrino (V)—A neutral particle of infinitesimally small rest mass emitted during beta plus or beta minus decay. This particle accounts for conservation of energy in beta plus and beta minus decays. It plays no role in damage from radiation. 

Americium does not exist in nature. All of its isotopes are man-made and radioactive. Americium-241 is produced by bombarding plutonium-239 with high-energy neutrons, resulting in the isotope plutonium-240 that again is bombarded with neutrons and results in the formation of plutonium-241, which in turn finally decays into americium-241 by the process of beta decay. Both americium-241 and americium-243 are produced within nuclear reactors. The reaction is as follows Pu + (neutron and X gamma rays) —> " Pu + (neutron and X gamma rays) —> Pu—> Am + beta minus ([ -) followed by " Am—> jNp-237 + Hej (helium nuclei). 

The pure metal of berkelium does not exist in nature and has never been directly artificially produced, although the first isotope of berkelium produced was berkelium-243. It was artificially formed by bombarding americium-241 with the nuclei of helium (alpha particles), as follows " Am+lalpha particle = 2 protons + 2 neutron)—> Bk. (Note Two protons as well as two neutrons are found in the nucleus of helium, and thus the two protons changed the atomic number of americium [ jAm] to berkelium [j Bk].) Today a different process is used to produce berkelium in small amounts, as follows Cm+(5n = neutrons X = gamma rays) —> (becomes) —> Bk + P- = (beta-minus decay). 

The second type of decay, called beta decay (fi decay), comes in three forms, termed beta-plus, beta-minus, and electron capture. All three involve emission or capture of an electron or a positron (a pcirticle with the tiny mass of an electron but with a positive chcirge), and all three also change the atomic number of the daughter atom. 

Beta-minus Beta-minus decay essentially mirrors beta-plus decay. A neutron converts into a proton, emitting an electron and an anftneutrino (which has the same symbol as a neutrino except for the line on top). Particle and antiparticle pairs such as neutrinos and antineutrinos are a complicated physics topic, so we ll keep it basic here by saying that a neutrino and an antineutrino would annihilate one another if they ever touched, but they re otherwise very similar. Again, the mass number remains the same after decay because the number of nucleons remains the same. However, the atomic number increases by 1 because the number of protons increases by 1 ... 

Ba+ je+v. Type beta-minus. You can identify this reaction as beta-minus due to... 

Technetium is a synthetic element, unknown in Nature. Its most useful isotope is produced by neutron bombardment of the 9KMo stable isotope in the form of the Mo042 ion to give the Tc04 " ion via a neutron-in, beta minus particle-out" process [9SMo(/i,p ) WmTc]. 

Beta decay is a general term applied to radioactive decay processes that result in the mass number A remaining constant while the atomic number Z changes. There are three types of beta decay beta-minus (/3 ) decay, positron (/3+) decay, and electron capture decay. It should be mentioned that (3 decay is often referred to as just beta decay, which is not strictly correct, because it is only one type of beta decay. 

Beta-Minus Decay. Beta-minus decay is the radioactive decay process in which a nucleus emits an electron (also known as a beta particle, j3, or e ) and an antineutrino (v), which is a very weakly interacting particle with an extremely small mass. By weakly interacting, we mean neutrinos are so aloof from ordinary... 

Why does /3 decay occur Well, stable nuclei have stable ratios between the proton number and neutron number. These ratios are nontrivial to predict, and are arcane to the extent that they include the concept of magic numbers. 1 Beta-minus emission occurs because some nuclei have too many neutrons therefore /3 decay is energetically favorable, resulting in a reduction in the neutron-to-proton ratio. 

Beta-Minus Decay 370 Positron Decay 3 72 Electron Capture Decay 3 72 Gamma Ray Emission 373... 

Tay-Sachs disease is caused by the mutation of the alpha subunit of hexosaminidase A gene (HEXA). Deficitated hexosaminidases A and B produce 3 distinct clinical forms of ganglioside GM2 storage disease-Tay-Sachs disease, Sandhoff disease, and juvenile GM2-gangliosidosis. Hexosaminidase-A has a structure comprised of alpha-beta subunits and Tay-Sachs disease is the alpha-minus mutation, whereas Sandhoff disease is a beta-minus mutation (Beutler and Kuhl, 1975 Beutler et al., 1975). Subunit alpha is mapped to chromosome 15 (and beta to chromosome 5). Different levels of residual activities are correlated with the age of clinical onset Tay-Sachs disease, 0.1% of normal hexosaminidase late infantile,... 

Beta-minus (/8 ) particle n. A radioactive emissioji consisting of a high-energy electron, j e. 

Q-values (decay energies for different decay modes) for beta minus (QP—), electron capture (Qe), alpha (Qa), and proton decay (Qp) are from Audi and Wapstra (1995). Systematic values are shown in square brackets. 

Radioactive decay. (In a nuclear reactor, there are two primary modes of decay, beta minus decay and alpha decay. For the process of beta minus decay, a nucleus of mass number A and atomic number Z is transformed into another nucleus of mass number A but with atomic number Z + 1. Alpha decay, on the other hand, results in the loss of a helium nucleus leaving the original nucleus four A units and two Z units lighter.)... 

Radionuclides are, by definition, unstable and decay by one, or more, of the decay modes alpha, beta-minus, beta-plus, electron capture or spontaneous fission. Although strictly speaking a de-excitation rather than a nuclear decay process, we can include isomeric transition in that list from the mathematical point of view. The amount of a radionuclide in a sample is expressed in Becquerels -numerically equal to the rate of disintegration - the number of disintegrations per second. We refer to this amount as the activity of the sample. Because this amount will change with time we must always specify at what time the activity was measured. 

Beta Particle Emission (Beta-minus or Radiation)... 

I Beta radiation is also called beta-minus (/3 ) radiation beoause of its negative charge. 

Note that the nuclear reaction is balanced, as previously described. It turns out that there are two types of beta decay, beta-plus decay (which produces a positron) and beta-minus decay (which produces an ordinary electron). Note, however, that this electron, although indistinguishable from any other electron, is the product of the decay, or the falling apart, of a nucleus. Beta-minus and beta-plus decays are denoted by placing a )8 or a over the arrow. Tritium decays by beta-minus decay, as shown in Equation (10.16) ... 

The half-lives of uranium-238 with respect to alpha decay, tritium with respect to beta-minus decay, and boron-8 with respect to beta-plus decay are 4.51 X 10 (4.51 billion) years, 12.3 years, and 0.77 years, respectively. 

Carbon-14 decays via beta-minus emission with a half-life of5730 years. Write a nuclear equation for this process. 

Potassium-40 decays via both beta-minus and beta-plus emission. Write a nuclear equation for each process. 

Uranium-233 is also a fissionable isotope. It is produced by the neutron bombardment of thorium-232 (to produce thorium-233), followed by two beta-minus emissions. Write nuclear equations representing these three processes. 

Lead-210 decays via alpha emission, and mercury-206 decays via beta-minus emission. Is it possible to transmute lead into gold using these two decay schemes Show equations to support your answer. 

Other applications of these elements take advantage of their nuclear properties. For example, one prevalent method of establishing the age of early humanoids is the potassium-argon dating procedure developed in the 1950s. Potassium-40 has a half-life of 1.3 billion years and decays by either beta-minus or beta-plus emission, as shown in Equations (12.22) and (12.23) ... 

Although francium is the product of the alpha decay of actinium, the majority of actinium nuclei decay by beta-minus emission. Write an equation for this process. 

Radium is both an alpha-particle and a beta-minus-particle emitter. Write an equation for its beta decay. 

Radium is a decay product of uranium-238, which undergoes successive alpha, beta, beta, alpha, and alpha decays. Write the five equations representing this sequential decay. All the beta emissions involve beta-minus particles. 

In the immediate aftermath of the Chernobyl nuclear power plant disaster in 1986, there was concern about the amount of strontium-90, cesium-137, cesium-135, and iodine-131 in the resulting radioactive plume. Iodine-131 is a beta-minus emitter Avith a half-life of 8.0 days. Write an equation for its decay and discuss the dangers it might pose as compared with strontium-90. 

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