Transmutation, of elements

The uranium disintegration series. iU decays by a series of alpha (a) and beta (p) emissions to the stable nuclide Pb. 

Transmutation is the conversion of one element into another by either natural or artificial means. Transmutation occurs spontaneously in natural radioactive disintegrations. Alchemists tried for centuries to convert lead and mercury into gold by artificial means, but transmutation by artificial means was not achieved until 1919, when Ernest Rutherford succeeded in bombarding the nuclei of nitrogen atoms with alpha particles and produced oxygen nuclides and protons. The nuclear equation for this transmutation can be written as 

It is believed that the alpha particle enters the nitrogen nucleus, forming gF as an intermediate, which then decomposes into the products. 

Rutherford s experiments opened the door to nuclear transmutations of all kinds. Atoms were bombarded by alpha particles, neutrons, protons, deuterons (iH), electrons, and so forth. Massive instruments were developed for accelerating these particles to very high speeds and energies to aid their penetration of the nucleus. The famous cyclotron was developed by E. O. Lawrence (1901-1958) at the University of California later instruments include the Van de Graaf electrostatic generator, the betatron, and the electron and proton synchrotrons. With these instruments many nuclear transmutations became possible. Equations for a few of these are as follows  

Electrons and positrons are accelerated along the tunnels at the Stanford Linear Accelerator Center. 

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Unstable isotopes decompose (decay) by a process referred to as radioactivity. Ordinarily the result is the transmutation of elements the atomic number of the product nucleus differs from that of the reactant. For example, radioactive decay of produces a stable isotope of nitrogen, N. The radiation given off (Figure 2.6) may be in the form of—... 

Nuclear reactions usually involve the transmutation of elements. 

Fig. 1.1. Relative abundances of the unchangeable elements in the universe (based on log (abundance of Si) = 6). Filled circles ( ), even atomic numbers open circles (o), odd atomic numbers. ( Unchangeable refers here to atoms of elements. Thus we ignore, for the purposes of this book, any transmutation of elements.)...

Using the elements mentioned in Section 22-13, induced radiation and the artificial transmutation of elements occur with both light elements, like the nonmetals 3H, 12C and 170 as well has heavier elements, like 97Tc, mFr, 210At and 239U, which can be metals, metalloids or nonmetals. Transuranium elements, i.e. the elements with atomic numbers greater than 92 (uranium), must be prepared by nuclear bombardment of other elements. 

Sensational Interest, to Ramsay s Transmutation of Elements. New York Times (August 18, 1907) SM9. 

It has been known for many years that the fission products observed in the field or in the laboratory some time after the event are in fact not usually the species produced in fission at all but the result of one or several consecutive beta disintegrations of shorter lived isobaric precursors which are formed directly in the fission process. From the chemist s point of view this is important because the f -decay process is an actual transmutation of elements, and the time scale involved is frequently comparable with that for the formation of fallout particles. 

The transmutation of elements, the conversion of one element into another, particularly of lead into gold, was the dream of the alchemists and one of the roots of modern chemistry. However, the alchemists had access only to chemical techniques, which proved ineffective, because they involved energy changes too weak to dislodge nucleons from nuclei. Transmutation has now been recognized in nature and achieved in the... 

Note on Radioactivity and the Transmutation of Elements. For centTiries, before the development of chemistry as -a science, the alchemists strove to carry out the transmutation of elements, in particular to change mercury into gold with the aid of the philosopher s stone. Then, as scientific chemistiy developed and success in transmutation eluded the investigators, the opinion gained firm hoki that the conversion of one element into another was impossible, and that atoms were immutable and indestructible. The definitions of element and elementary substance accepted during the nineteenth century were based upon this belief. 

One thing you might have noticed was the use of the word transmuted meaning the inter-conversion of one element into another. The ancient alchemists were always trying to do this, their main object was to transmute cheap lead into gold. But they never achieved it. Transmutation of elements was going on all around them if they only knew it, but not lead into gold . Well, not yet. 

Nuclei with Atomic Number Greater Than 83 Detection of Radiation Rates of Decay and Half-Life Disintegration Series Uses of Radionuclides Artificial Transmutations of Elements Nuclear Fission Nuclear Fission Reactors Nuclear Fusion... 

Chemical properties are determined by electron distributions and are only indirectly influenced by atomic nuclei. Until now, we have discussed ordinary chemical reactions, so we have focused on electron configurations. Nuclear reactions involve changes in the composition of nuclei. These extraordinary processes are often accompanied by the release of tremendous amounts of energy and by transmutations of elements. Some differences between nuclear reactions and ordinary chemical reactions follow. 

The electron produced in beta decay is not one of the original electrons from outside the nucleus. It is produced by the change of a neutron into a proton and an electron. Whenever beta decay occurs, transmutation of elements occurs. The decaying nucleus turns into the nucleus of an element with an atomic number that is 1 greater than that of the original and a mass number that is the same. 

Notice that transmutation of elements has occurred. An atom of carbon-14 is converted into an atom of nitrogen-14. Because the beta particle has only the mass of an electron, the mass number remains 14. Because the beta decay changes a neutron to a proton, the atomic number of the nucleus increases by one unit, from 6 to 7. The atomic number on the left side of the equation, 6, is the same as the sum on the right side of the equation (6 = 7 + ( — 1)). The nuclear equation as a whole is balanced. 

Equations for Nuclear Reactions 26-13 Artificial Transmutations of Elements... 

The idea of transmutation of elements in the natural decay chains did not accompany the discovery of radioactivity by Becquerel. However, Marie and Pierre Curie extended the investigations of Becquerel using a variety of... 

Solar systems, or direct diabolic intervention, the writer feels that the exothermic argument is so strong that he, hesitantly, must look for other explanations such as collective hypnosis. Anyhow, for Crookes living 100 years ago, there was still enough of a connection with pre-scientific ideas that he suspected a maturation of the meta-elements in minerals. By the way, this is one of the rare cases of older history being optimistic and newer ideas pessimistic with exception of nuclear physics directed by human beings, the only transmutation of elements on Earth is the irreversible and uninfluenced natural radioactivity of which the chains mranium 238 to lead 206, thorium 232 to lead 208, and the rare isotope potassium 40 to argon 40 (1 percent of the atmosphere) and calcium 40 have a perceptible influence on the heat balance of the crust. 

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