Quick Facts
| Property | Value |
|---|---|
| Symbol | Pa |
| Atomic Number | 91 |
| Atomic Mass | 231.04 u |
| Category | Actinide |
| Period | 7 |
| Group | 3 |
| Block | f |
| Electron Configuration | [Rn] 5f² 6d¹ 7s² |
History and Discovery
Discovered by: Kasimir Fajans and Oswald Helmuth Göhring Year of Discovery: 1913 Location: Karlsruhe, Germany
Etymology
From Greek "protos" (first) + actinium, as it decays into actinium.
Properties
- Highly radioactive
- Very rare (rarer than radium)
- Extremely toxic
- Has no practical applications
Interesting Facts
- One of the rarest and most expensive elements
- Named for being the parent of actinium
- Highly radioactive and toxic
- Only about 500 grams exist worldwide
- Very difficult to study due to radioactivity