The answers that apply;
- may involve a change in total mass
- involve very high-energy changes
- involve changes in nuclides when decay occurs
There are two types of radioactive reactions; fission and fusion. Fission involves the splitting of an unstable isotope (with a high mass number) into stable elements (of lower mass number) that differ in characteristics from the parent atoms. Fusion involves the fusion of two light atoms into a heavier atom. Both reactions emit huge quantities of energy in the process.