Most of the natural occurring (isotopes of) elements are NOT radioactive.
Though most of all the known isotopes are radioactive but most of them do NOT naturally occur.
Radioactive elements make up a small fraction of all naturally occurring elements in Earth's crust. Most elements are stable and non-radioactive. However, even though they are a minority, radioactive elements play important roles in various scientific, medical, and industrial applications.
Most of them do. Radon probably does not.
1. astatine is a halogen that is radioactive.
Group 3 of the periodic table contains many of the radioactive elements.
All of the actinides are radioactive, and almost all are synthetic.
No, trace elements are not necessarily radioactive. A link to a list of elements that have no natural radioactive isotopes is at a related question, below.
After disintegration all radioactive elements are transformed in other elements.
Some examples of radioactive elements on the periodic table include uranium, thorium, radium, and plutonium. These elements have unstable atomic nuclei that decay over time, emitting radiation in the process.
All radioactive elements are unstable. Most isotopes of elements in periodic table are radioactive. Overall, most of the elements are unstable but they are present in traces on earth. Most elements on earth are stable.
No. All elements with atomic number greater than 83 are radioactive, including some metals such as polonium, uranium, etc. But there are radioactive isotopes of most metals on the periodic table but are very rare and sometimes must be produced in reactor or particle accelerator.
Not all of the transition elements are radioactive. Many of them are, and some of them have common radioactive isotopes, but some of them have no naturally occurring radioactive isotopes. Please note that all elements have synthetic radioactive isotopes, at least.
Radioactive elements