Radioactive elements
The element you selected is a radioactive element.
Radioactive elements are not stable and are transformed to other elements. There are several routes of transformation:
- emission of alpha particles (helium nuclei)
- emission of beta particles (electrons)
- electron capture by nucleus
- breakdown of atoms (fission to smaller nuclei)
The speed of breakdown, expressed as radioactive half-life, varies between nanoseconds and billions of years. More on this can be found in literature.
None of the radioactive elements (with the possible exception of depleted uranium) is available to the public in relevant quantities. Working with these elements requires very sophisticated equipment and really tight safety and security measures.