91
231.036 u
Pa
Protactinium
Actinide
Atomic Structure
Physical State
Group
N/A
Period
7
Block
f
Electron Configuration
[Rn] 5f² 6d¹ 7s²
Physical Properties
Atomic Mass:
231.036 u
Electronegativity:
1.5
Atomic Radius:
200 pm
Ionization Energy:
5.89 eV
Density:
15.37 g/cm³
Melting Point:
1841 K
Boiling Point:
4300 K
Historical Information
Discovered By:
William Crookes
Year Discovered:
1913