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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 ...
Lead-213 also occurs in the decay chain of neptunium-237. Lead-210 is particularly useful for helping to identify the ages of samples by measuring its ratio to lead-206 (both isotopes are present in a single decay chain). [51] In total, 43 lead isotopes have been synthesized, with mass numbers 178–220. [38]
38 isotopes of lead have been discovered. 9 of these are naturally occurring. The most common isotope is lead-208, followed by lead-206, lead-207, and lead-204: all of these are stable. 5 isotopes of lead occur from the radioactive decay of uranium and thorium. These isotopes are lead-209, lead-210, lead-211, lead-212 and lead-214. [18]
Lead consists of four stable isotopes: 204 Pb, 206 Pb, 207 Pb, and 208 Pb. Local variations in uranium/thorium/lead content cause a wide location-specific variation of isotopic ratios for lead from different localities. Lead emitted to the atmosphere by industrial processes has an isotopic composition different from lead in minerals.
Lead is perhaps the best example of a partly radiogenic substance, as all four of its stable isotopes (204 Pb, 206 Pb, 207 Pb, and 208 Pb) are present primordially, in known and fixed ratios. However, 204 Pb is only present primordially, while the other three isotopes may also occur as radiogenic decay products of uranium and thorium.
The decay chain from lead-212 down to lead-208, showing the intermediate decay products. In this example: 234 Th, 234m Pa,..., 206 Pb are the decay products of 238 U. 234 Th is the daughter of the parent 238 U. 234m Pa (234 metastable) is the granddaughter of 238 U. These might also be referred to as the daughter products of 238 U. [1]
Of the 26 "monoisotopic" elements that have only a single stable isotope, all but one have an odd atomic number—the single exception being beryllium. In addition, no odd-numbered element has more than two stable isotopes, while every even-numbered element with stable isotopes, except for helium, beryllium, and carbon, has at least three.
Thus, the only sources of lead in a zircon crystal are through decay of uranium and thorium. 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 ...