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Lead (82 Pb) has four observationally stable isotopes: 204 Pb, 206 Pb, 207 Pb, 208 Pb. Lead-204 is entirely a primordial nuclide and is not a radiogenic nuclide.The three isotopes lead-206, lead-207, and lead-208 represent the ends of three decay chains: the uranium series (or radium series), the actinium series, and the thorium series, respectively; a fourth decay chain, the neptunium series ...
Natural lead consists of four stable isotopes with mass numbers of 204, 206, 207, and 208, [38] and traces of six short-lived radioisotopes with mass numbers 209–214 inclusive. The high number of isotopes is consistent with lead's atomic number being even.
Radon-222 itself alpha decays to polonium-218 with a half-life of approximately 3.82 days, making it the most stable isotope of radon. [1] Its final decay product is stable lead-206 . In theory, 222 Rn is capable of double beta decay to 222 Ra, and depending on the mass measurement, single beta decay to 222 Fr may also be allowed.
This page uses the meta infobox {{Infobox isotopes (meta)}} for the element isotopes infobox.. This infobox contains the table of § Main isotopes, and the § Standard atomic weight.
[2] [3] Technetium and promethium (atomic numbers 43 and 61, respectively [a]) and all the elements with an atomic number over 82 only have isotopes that are known to decompose through radioactive decay. No undiscovered elements are expected to be stable; therefore, lead is considered the heaviest stable element.
Specifically, 206 Pb is formed from 238 U, 207 Pb from 235 U, and 208 Pb from 232 Th. In rocks that contain uranium and thorium, the excess amounts of the three heavier lead isotopes allows the rocks to be "dated", thus providing a time estimate for when the rock solidified and the mineral held the ratio of isotopes fixed and in place.
Both the uranium-235 and uranium-238 series decay into an isotope of lead. The half-life of converting 235 U to 207 Pb is 710 million years, and the half-life of converting 238 U to 206 Pb is 4.47 billion years. Because of high resolution mass-spectroscopy, both chains can be used to date rocks, giving complementary information about the rocks.
204 Pb is the only non-radiogenic lead isotope, therefore is not one of the daughter isotopes. These daughter isotopes are the final decay products of U and Th radioactive decay chains beginning from 238 U (half-life 4.5 Gy), 235 U (half-life 0.70 Gy) and 232 Th (half-life 14 Gy) respectively. With the progress of time, the final decay product ...