Radioactive isotopes are an interesting part of the world of chemistry. They are found everywhere in nature, and can also be created by people using nuclear reactions. Among the most common sources that play an important role in the Earth's ecosystem are nuclear reactors and natural sources of nuclear fusion. Of course, knowledge about the essence of radioactive isotopes and the dangers associated with them is necessary not only for studying at school and universities, but also for other scientific professions, especially physics and medicine. Today we will tell you more about radioactive chemical elements.