What is the element with a mass number of 222?

1 Answer
Sep 15, 2016


#""^222Rn# has #Z=86#. While this is an inert gas, the actual atom is unstable with respect to radioactive decay. Much of our radiation exposure is due to radon. Please note that there might be other elements with an isotope whose mass is #222" amu"#. Francium perhaps?