For a radioactive nucleus that undergoes ^+ decay, which of the following CANNOT occur?

Step-by-step solution

In ^+ decay, a proton inside the nucleus is converted into a neutron, a positron, and an electron neutrino. The nuclear reaction is represented as: ^ A _ Z X ^ A _ Z-1 Y + e^+ + _e The atomic number Z decreases by 1 , so a nucleus with a lower atomic number is produced. The mass number A remains unchanged, meaning the daughter nucleus is an isobar of the original nucleus. Since the atomic number changes, the daughter nucleus cannot be an isotope of the original nucleus, as isotopes must have the same atomic number.