Lead and bismuth are the most massive naturally occurring elements;

Lead and bismuth are the most massive naturally occurring elements; Every nucleus more massive than them eventually decays into one form or another of lead or bismuth. The sequence of isotopes along the way forms a decay series or disintegration series. For two points per series, given the final form of each series and the number of alpha (á) and beta (â-) decays, determine the starting nuclide of each series and enter it below. On the bottom and back of the paper, show one set of the steps along the way for each series. Don’t just Google the answer, but work out one of the many, many possibilities for each series. Final nuclide Number of á decays Number of â- decays lead-208 6 4 bismuth-209 8 5 lead-206 8 6 lead-207 7 4 Initial nuclide