Radioactive isotopes are atoms that are unstable and subsequently produce energy in a procedure called radioactive decay.
All the atoms of an element have a similar number of protons, however the quantity of their neutrons can contrast. On the off chance that this happens, at that point we can call these isotopes of an element. Isotopes have a similar number of protons, yet they contrast in the quantity of neutrons.
If an isotope has an unstable nucleus that separates to emanate radiation, at that point these are what we call radioactive isotopes, also called radioisotopes.