See the related questions below for each individual definition.
Curium has 20 isotopes and 7 isomers.
Seaborgium (Sg) has 17 isotopes - including isomers and metastable isotopes.
Americium has today (2011) 19 isotopes and 8 isomers.
Not isomers, Isotopes
Radium has today 33 isotopes and 12 nuclear isomers.
Chromium has 25 known isotopes, 2 isomers, 3 of which are non-radioactive.
Francium has approx. 40 isotopes and nuclear isomers.
Uranium has 3 natural isotopes and 26 artificial isotopes and isomers..
Actinium has 36 isotopes and 7 nuclear isomers.
Two isomers of technetium were used in medicine.
1. Americium has 19 isotopes aqnd 8 isomers known today; for the complete list see the link below. 2. Isotope: an atom of an element having different number of neutrons.
Radium has today 33 isotopes and 12 nuclear isomers.