What is Mononuclidic element?
[[File:Monoisotopic, mononuclidic, radioactive elements.svg|thumb|336px|The green elements, plus [[bismuth]] (orange) and [[protactinium]] (red), are mononuclidic.]] A '''mononuclidic element''' or '''monotopic element''' is a [[Chemical element|chemical elements]] that is found [[Nature|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) {{Chemistry-stub}} [[Category:Isotopes]]