protactinium

Traductions

• anglais

  Date : 1983

  Définition

  An element. State: solid; group: IIIB (actinide series); atomic no.: 91; atomic Wt.: 231.0359, valence: 4,5: isotopes: 2 natural radioactive. A radioactive element whose longest-lived isotope is 231, with a half-life of about 106 years; it occurs naturally in trace quantities in uranium ores and is about as abundant as radium. The 133 isotope is made artificially by decay of a thorium isotope. It is a crystalline, whitish metallic solid (density 15.37 g/cc), but there is no present industrial use. Only a few compounds are known.

  Termes :

  1. protactinium
  2. Pa

  Terme associé :

  1. protoactinium