Pa
Protactinium
Actinide
Protactinium is a rare, highly radioactive metal that is extremely toxic and has no practical applications outside research.
Key Facts
Atomic Number
91
Atomic Weight
231.04
State
Solid
Half-life
32,760 years (Pa-231)
Discovered
1913
Kasimir Fajans and Otto Göhring
Overview
Description
Protactinium is a rare, highly radioactive metal that is extremely toxic and has no practical applications outside research.
Discovery
Protactinium was discovered in 1913 by Kasimir Fajans and Otto Göhring.