Difference between revisions of "Protactinium"

Atomic properties
Atomic number	91
Standard atomic weight	231.035 88(2)
Electron configuration	[Rn] 5f2 6d1 7s2
Physical properties
Melting point	1565(19) °C (1838 K)
Boiling point	ca. 4227 °C (4500 K)
Density	15.37(8) g cm−3
Electric resistivity	19.1 × 10−6 Ω cm
Ionization energy
	5.89(12) eV; 568(12) kJ mol−1
Atomic radii
Covalent radius	200 pm
Metallic radius	163 pm
Ionic radius	92 pm (Pa5+, Oh)
Thermodynamic properties
Enthalpy change of fusion	16.7 kJ mol−1
Enthalpy change of vaporization	481 kJ mol−1
Miscellaneous
CAS number	7440-13-3
	Where appropriate, and unless otherwise stated, data are given for 100 kPa (1 bar) and 298.15 K (25 °C).
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Revision as of 15:14, 13 April 2011

thorium ← protactinium → uranium

Pr
↑
Pa
↓
—

Protactinium (symbol: Pa) is a member of the actinoid series of chemical elements.

↑ The configuration [Rn] 5f¹ 6d² 7s² is given as a possible alternative in some textbooks.

↑ ^1.0 ^1.1 Myasoedov, Boris F.; Kirby, H. W.; Tananaev, Ivan G. Protactinium. In The Chemistry of the Actinide and Transactinide Elements, 3rd ed.; Morss, Lester R.; Edelstein, Norman M.; Fuger, Jean, Eds.; Springer: Dordrecht, the Netherlands, 2006; Vol. 1, Chapter 4, pp 161–252. doi:10.1007/1-4020-3598-5_4, <http://radchem.nevada.edu/classes/rdch710/files/protactinium.pdf>.
↑ ^2.0 ^2.1 Greenwood, Norman N.; Earnshaw, A. Chemistry of the Elements; Pergamon: Oxford, 1984; pp 1450–86. ISBN 0-08-022057-6.
↑ Sugar, Jack Ionization energies of the neutral actinides. J. Chem. Phys. 1973, 59, 788–91. DOI: 10.1063/1.1680091. Sugar, Jack Revised ionization energies of the neutral actinides. J. Chem. Phys. 1974, 60, 4103. DOI: 10.1063/1.1680874.
↑ Cordero, Beatriz; Gómez, Verónica; Platero-Prats, Ana E.; Revés, Marc; Echeverría, Jorge; Cremades, Eduard; Barragán, Flavia; Alvarez, Santiago Covalent radii revisited. Dalton Trans. 2008 (5), 2832–38. DOI: 10.1039/b801115j.
↑ Shannon, R. D. Revised effective ionic radii and systematic studies of interatomic distances in halids and chalcogenides. Acta Crystallogr. A 1976, 32 (5), 751–67. DOI: 10.1107/S0567739476001551.

See also the corresponding article on Wikipedia.

@@ Line 7: / Line 7: @@
 |below = —
 |atomic-number = 91
-|configuration = [Rn] 5f<sup>2</sup> 6d<sup>1</sup> 7s<sup>2</sup> {{#tag:ref| The configuration {{nowrap|[Rn] 5f<sup>1</sup> 6d<sup>2</sup> 7s<sup>2</sup>}} is given as a possible alternative in some textbooks.|group=note}}
+|atomic-weight = 231.035 88(2)
+|configuration = [Rn] 5f<sup>2</sup> 6d<sup>1</sup> 7s<sup>2</sup> {{#tag:ref|The configuration {{nowrap|[Rn] 5f<sup>1</sup> 6d<sup>2</sup> 7s<sup>2</sup>}} is given as a possible alternative in some textbooks.|group=note}}
 |phys-ref = <ref name="MKT">{{citation | last1 = Myasoedov | first1 = Boris F. | last2 = Kirby | first2 = H. W. | last3 = Tananaev | first3 = Ivan G. | contribution = Protactinium | title = The Chemistry of the Actinide and Transactinide Elements | editor1-first = Lester R. | editor1-last = Morss | editor2-first = Norman M. | editor2-last = Edelstein | editor3-first = Jean | editor3-last = Fuger | edition = 3rd | year = 2006 | volume = 1 | publisher = Springer | location = Dordrecht, the Netherlands | chapter = 4 | pages = 161–252 | url = http://radchem.nevada.edu/classes/rdch710/files/protactinium.pdf | doi = 10.1007/1-4020-3598-5_4}}.</ref><ref name="G&E">{{Greenwood&Earnshaw1st|pages=1450–86}}.</ref>
 |melting-point = 1565(19)&nbsp;°C (1838&nbsp;K)