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Protactinium

91
Pa
231.0359
Protactinium
 General | States | Energies | Oxidation & Electrons | Appearance & Characteristics | Reactions | Other Forms Radius | Conductivity | Abundance

General:

Name: Protactinium Symbol: Pa
Group: Rare Earth, Actinides Atomic weight: 231.0359
Density @ 293 K: 15.4 g/cm3 Atomic volume: 15.0 cm3/mol
Group: Rare Earth, Actinides discovered: 1917

States:

state (s, l, g): s
melting point: 1873.2 K boiling point: 4500 K
Heat of fusion: 12.30 kJ/mol Heat of vaporization: ?

Energies:

1st ionization energy: 568 kJ/mole
electronegativity: 1.5 2nd ionization energy: kJ/mole
electron affinity: kJ/mole 3rd ionization energy: kJ/mole
Specific heat: 0.12 J/gK heat atomization: 527 kJ/mole atoms

Oxidation & Electrons:

Shells: 2,8,18,32,20,9,2 electron configuration: [Rn] 5f2 6d1 7s2
minimum oxidation number: 0 maximum oxidation number: 5
min. common oxidation no.: 0 max. common oxidation no.: 5

Appearance & Characteristics:

structure: fcc: face-centered cubic color: silvery
uses: toxicity:
hardness: mohs characteristics: Radioactive

Reactions:

reaction with air:
reaction with 6M HCl: reaction with 6M HCl:
reaction with 15M HNO3: reaction with 6M NaOH: none

Other Forms:

number of isotopes: 1 hydride(s): PaH3
oxide(s): PaO PaO2 Pa2O5 chloride(s): PaCl4 PaCl5

Radius:

ionic radius (2- ion): pm ionic radius (1- ion): pm
atomic radius: 163 pm ionic radius (1+ ion): pm
ionic radius (2+ ion): pm ionic radius (3+ ion): 118 pm

Conductivity:

thermal conductivity: J/m-sec-deg
electrical conductivity: 1/mohm-cm polarizability: 25.4 A^3

Abundance:

source: Synthetic(U-235 decay)
rel. abund. solar system: log abundance earth's crust: -5.9 log
cost, pure: $/100g cost, bulk: $/100g