What transition metals are radioactive?
Tc, Lr, Rf, Db, Sg, Bh, Hs, Mt, Ds, Rg, and Cn
The transition metals are the yellow elements in the middle of the periodic table. When looking at a periodic table, the atomic mass of each element is shown; for example, carbon has an atomic mass of 12.011. When atoms have no known stable isotopes, the atomic number is displayed as a whole number in parenthesis, such as for technetium: (98). While certain isotopes of all elements can be radioactive, an element is considered radioactive if it has no stable isotopes. The transition metals with no stable isotopes are:
Tc, Lr, Rf, Db, Sg, Bh, Hs, Mt, Ds, Rg, and Cn. Notice that all except Tc are transuranic, meaning that their atomic number is greater than 92.