Protactinium Elemental Symbol
Protactinium



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Protactinium Protactinium Protoattinio Protacnídio Protactinio Protaktinium

Protactinium Bohr ModelProtactinium is a radioactive actinide group metal with the atomic symbol Pa, atomic number 91, and atomic weight 231. It decays by alpha-emission. It is a Block F, Group 3, Period 7 element. The number of electrons in each of Protactinium's shells is 2, 8, 18, 32, 20, 9, 2 and its electron configuration is [Rn] 5f2 6d1 7s2. It has an atomic radius of 163.pm and a Van der Waals radius is 243.pm. In its elemental form protactinium's CAS number is 7440-13-3. It is found in the form of two isotopes: protactinium-231 and protactinium-234. Protactinium was first predicted by Dmitri Mendeleev in 1869 and first isolated by William Crookes in 1900. It was named by Otto Hahn and Lise Meitner  in 1917. The name Protactinium originates from the Greek word 'Porots' which means first.

Protactinium is both toxic and radioactive. Protactinium information, including technical data, safety data and its high purity properties, research, applications and other useful facts are discussed below. Scientific facts such as the atomic structure, ionization energy, abundance on earth, conductivity and thermal properties are included.


  • Properties
  • Research
  • Isotopes
  • Other Elements

Protactinium Properties


GENERAL PROPERTIES   PHYSICAL PROPERTIES  
Symbol: Pa Melting Point: 1572 oC, 2861.6 oF, 1845.15 K
Atomic Number: 91 Boiling Point: Unknown
Atomic Weight: 231 Density: 15370  kg m-3
Element Category: Actinide Liquid Density @ Melting Point: N/A
Group, Period, Block: n/a, 7, f Specific Heat: N/A
    Heat of Vaporization 481 kJ·mol−1
CHEMICAL STRUCTURE Heat of Fusion 12.34 kJ·mol−1
Electrons: 91 Thermal Conductivity: 47 W·m−1·K−1
Protons: 91 Thermal Expansion: N/A
Neutrons: 122 Electrical Resistivity: (0 °C) 177 nΩ·m
Electron Configuration: [Rn] 5f26d17s2 Electronegativity: 1.5 (Pauling scale)
Atomic Radius: 163 Tensile Strength: N/A
Covalent Radius: 200 Molar Heat Capacity: N/A
Van der Waals radius: 243 pm Young's Modulus: N/A
Oxidation States: 5, 4, 3, 2, 0 Shear Modulus: N/A
Phase: Solid  Bulk Modulus: N/A
Crystal Structure: tetragonal Poisson Ratio: N/A
Magnetic Ordering: paramagnetic Mohs Hardness: N/A
1st Ionization Energy: 568 kJ·mol−1 Vickers Hardness: N/A
2nd Ionization Energy: N/A Brinell Hardness: N/A
3rd Ionization Energy: N/A Speed of Sound: N/A
       
IDENTIFIERS   MISCELLANEOUS  
CAS Number: 7440-13-3 Abundance in typical human body, by weight: N/A
ChemSpider ID: 22387 Abundance in typical human body, by atom: N/A
PubChem CID: 23945 Abundance in universe, by weight: N/A
MDL Number: N/A Abundance in universe, by atom: N/A
EC Number: N/A Discovered By: William Crookes
Beilstein Number: N/A Discovery Date: 1900
SMILES Identifier: [Pa]  
InChI Identifier: InChI=1S/Pa Other Names: Protoattinio, Protaktinium
InChI Key: XLROVYAPLOFLNU-UHFFFAOYSA-N  
       
       
       
       
       


Recent Research & Development for Protactinium

  • M.V. Di Giandomenico, C. Le Naour, Complex formation between protactinium(V) and sulfate ions at 10 and 60 °C, Inorganica Chimica Acta, Volume 362, Issue 9, 1 July 2009
  • Marcus Christl, Lukas Wacker, Jörg Lippold, Hans-Arno Synal, Martin Suter, Protactinium-231: A new radionuclide for AMS, Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, Volume 262, Issue 2, September 2007
  • J Fietzke, A Bollhöfer, N Frank, A Mangini, Protactinium determination in manganese crust VA13/2 by thermal ionization mass spectrometry (TIMS), Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, Volume 149, Issue 3, February 1999
  • Y Tahri, H Chermette, N El Khatib, J.C Krupa, E Simoni, Electronic structures of thorium and protactinium halide clusters of [ThX8]4- type, Journal of the Less Common Metals, Volume 158, Issue 1, 15 February 1990
  • David M. Taylor, Arnulf Seidel, Felicitas Planas-Bohne, Ute Schuppler, Margarethe Neu-Mlüler, Rainer E. Wirth, Biochemical studies of the interactions of plutonium, neptunium and protactinium with blood and liver cell proteins, Inorganica Chimica Acta, Volume 140, 15 December 1987
  • Marcos Solache-Rios, Alfred G. Maddock, Some complexes of protactinium with polydentate ligands, Journal of the Less Common Metals, Volume 122, August 1986
  • P.D Kleinschmidt, J.W Ward, Thermochemical studies on the plutonium fluorides and protactinium ovides, Journal of the Less Common Metals, Volume 121, July 1986
  • R Bett, J.C Spirlet, W Müller, The electrical resistivity of protactinium, Journal of the Less Common Metals, Volume 102, Issue 1, September 1984
  • C. Golian, T. Nightingale, P.L. Airey, Protactinium-231 measurement and application to a uranium series transport model, Nuclear Instruments and Methods in Physics Research, Volume 223, Issues 2–3, 15 June 1984
  • John M. Haschke, Wilhelm Bartscher, Jean Rebizant, John W. Ward, Phase relations and structures of protactinium hydrides, Inorganica Chimica Acta, Volume 94, Issues 1–3, February 1984
  • J.C. Spirlet, E. Bednarczyk, W. Müller, The preparation of protactinium metal on the gram scale, Journal of the Less Common Metals, Volume 92, Issue 2, August 1983
  • A Wojakowski, D Damien, Y Hery, Phosphures de protactinium PaP2 et Pa3P4, Journal of the Less Common Metals, Volume 83, Issue 2, February 1982
  • M.H Bradbury, The vapour pressure of protactinium metal, Journal of the Less Common Metals, Volume 78, Issue 2, April 1981
  • M.S.S. Brooks, G. Calestani, J.C. Spirlet, J. Rebizant, W. Müller, J.M. Fournier, A. Blaise, f-Electron contribution to bonding in protactinium compounds, Physica B+C, Volume 102, Issues 1–3, October–December 1980
  • G. Calestani, J.C. Spirlet, J. Rebizant, W. Müller, Preparation and single-crystal growth of protactinium arsenides by chemical vapour transport, Journal of the Less Common Metals, Volume 68, Issue 2, December 1979
  • D. Brown, The polymorphism of protactinium pentabromide, Inorganic and Nuclear Chemistry Letters, Volume 15, Issues 5–6, 1979
  • D. Brown, B. Whittaker, A new simple procedure for the recovery and purification of protactinium-231, Journal of the Less Common Metals, Volume 61, Issue 1, September 1978
  • J. Bohet, W. Müller, Preparation and structure studies of “Van Arkel” protactinium, Journal of the Less Common Metals, Volume 57, Issue 2, February 1978
  • J. Fuger, J. Bohet, W. Muller, B. Whittacker, D. Brown, The enthalpy of solution of body-centred tetragonal protactinium metal, Inorganic and Nuclear Chemistry Letters, Volume 14, Issue 1, 1978
  • M.F. Le Cloarec, A. Cazaussus, Preparation and properties of tetravalent protactinium phosphates, Journal of Inorganic and Nuclear Chemistry, Volume 40, Issue 9, 1978

Protactinium Isotopes


Protactinium has three naturally occurring isotopes, none of them are stable.