436 atoms of Pb 207 are left in the rock.
Alpha and beta decays are the mechanism through which uranium transforms into the lead. While 235U and its daughter nuclides only experience seven alpha and four beta decays, 238U and its daughter nuclides suffer eight alpha and six beta decays overall.
When there are too few neutrons in relation to protons, alpha decay occurs. There is the discharge of an alpha particle, which consists of two protons and two neutrons.
When there are more neutrons than protons, beta decay can happen. A high-speed electron is ejected from a proton that transforms spontaneously from a neutron.
Since gamma radiation is emitted as a wave rather than a particle, the atomic structure of an atom remains unaltered. Atomic fission is the primary cause of neutron emission. At one time, many neutrons can be released.
Learn more about radioactive decay here:
https://brainly.com/question/1365848
#SPJ4
