Which element has no stable isotopes?

Well, its when there is more than one number for atomic mass,(the number at the top). So for an atom to have no stable isotopes means that it only has one atomic mass, like aluminum for example. read more

Elements with no stable isotopes include technetium (element 43) and promethium (element 61) and all elements heavier than lead (elements 83 and higher). Bismuth, element 83, is virtually stable with an extremely long half life of 1.9 x 1019 years. read more

Of the chemical elements, only one element has 10 such stable isotopes, one has eight isotopes, four have seven isotopes, eight have six isotopes, ten have five isotopes, nine have four isotopes, five have three stable isotopes, 16 have two stable isotopes, and 26 have a single stable isotope. read more