Protactinium
Elemental State Pa
Electron Configuration 1s22s22p63s23p63d104s24p64d104f145s25p65d106s26p67s26d15f2
First Ionization Potential 5.89 eV
Electron Affinity  
Z*  
Pauling Electronegativity 1.5
Covalent Radius  
Metallic Radius 1.63 Å
Ionic Radius  
van der Waal's Radius  
Melting Point 1572 oC
Boiling Point  
Density 15.37 g/cm3 (calculated)
Other Properties All isotopes are radioactive

231Pa half-life = 32500 years