what are radioactive isotopes
Jupiterimages/Creatas/Getty Images. Radioactive isotopes, also called radioisotopes, are atoms with a different number of neutrons than is usual, making them unstable. A radioisotope's nucleus decays, emitting alpha, beta and gamma rays until the isotope reaches stability.Once itâs stable, the isotope may become another element entirely, such as when uranium decays into lead.ignificance. Radioactive isotopes are useful because they produce alpha, beta and gamma rays. The radiationâs penetrating power depends on its energy, particle mass, and the objectâs density. These properties lead to many practical applications in science, medicine and industry.