Mononuclidic element

A mononuclidic element or monotopic element is a chemical elements that is found naturally on Earth as only one nuclide. Most elements have many nuclides, that is their nuclei may have various numbers of neutrons. The single nuclide of a mononuclidic element may, or may not, be a stable one. There are 21 mononuclidic elements: nineteen are stable, and two are radioactive.

 Isotopes of mononuclidic elements 
 Beryllium-6
 Fluorine-18
 Sodium-23
 Aluminium-27
 Phosphorus-31
 Scandium-45
 Manganese-55
 Cobalt-59
 Arsenic-75
 Yttrium-89
 Niobium-93
 Rhodium-103
 Iodine-127
 Caesium-133
 Praseodymium-141
 Terbium-159
 Holmium-165
 Thulium-169
 Gold-197
 Bismuth-209 (very weakly radioactive)
 Protactinium-231 (radioactive)

Category:Isotopes