Decay natural radioactive family

The decay chain of the natural radioactive family arising from Th is shown in Figure 26.1-1. Th finally decays to the stable lead isotope Pb. 

The naturally radioactive elements usually decay by emitting alpha particles their final decay product is usually a stable isotope of Pb there are four such "families" (often with branching) ... 

The displacement law provided for harmonious relationship between radioactive families and the periodic system of elements. After several successive alpha and beta decays the originators of the families converted into stable lead giving rise in the process to the natural radioactive elements found between uranium and bismuth in the periodic table. But then each box in the system had to accommodate several radioelements. They had identical nuclear charges but different masses, that is, they looked as varieties of a given element with identical chemical properties but different masses and radioactive characteristics. In December 1913 Soddy suggested the name isotopes for such varieties of elements (from the Greek for the common place ) because they occupy the same box in the periodic system. 

In natural sources, all elements with an atomic number greater than 83 are radioactive, but most elements are present in very small concentrations. These radionuclides belong to chains of successive decay, and all of the species in one such chain constitute a radioactive family series. Three of these families include all of the natural activities in this region of the periodic chart [1]. The existence of branching decays in each of the three series should be noted. These representations only recognize the most common decomposition elements, but new decomposition branches have been discovered. 

The first member of this family, manganese, exhibits One of the most interesting redox chemistries known thus it has already been discussed in detail above. Technetium exhibits the expected oxidation states, and associated with these are modest emf values. All of the isotopes of technetium are radioactive but "Tc has a relatively long half-life (2.14 k 10s years) and is found in nature in small amounts because of the radioactive decay of uranium. Oxidation slates of rhenium range from +7 to - 3, with some species ReOj and Re3+) unstable with respect to disproportionation. 

Uranium, element 92, is a member of the actinide family of the periodic table, which includes elements 89-104. It has 3 primordial and 12 artificial or man-made isotopes, all of which are radioactive. The naturally occurring uranium series is headed by which subsequently decays... 

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