Задача 60057.

A certain radioactive series begins with an isotope containing 235 nucleons and ends with an isotope with atomic number 82, while it includes seven alpha decays and four beta decays. Determine the missing characteristics of the initial and final isotopes of the series. What elements do they belong to?

Detailed solution with a brief record of the conditions, formulas and laws used in the solution, derivation of the calculation formula and answer.
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