ప్రాసియోడిమియం, 00 Pr Pronunciation [ 1] (PRAY-zee -ə-DIM -ee ) Appearance grayish white
Group మూస:Infobox element/symbol-to-group/format Period period 6 Block f-block Electron configuration [Xe ] 4f3 6s2 Electrons per shell 2, 8, 18, 21, 8, 2 Phase at STP solid Melting point 1208 K (935 °C, 1715 °F) Boiling point 3793 K (3520 °C, 6368 °F) Density (near r.t. ) 6.77 g/cm3 when liquid (at m.p. ) 6.50 g/cm3 Heat of fusion 6.89 kJ/mol Heat of vaporization 331 kJ/mol Molar heat capacity 27.20 J/(mol·K) Vapor pressure
P (Pa)
1
10
100
1 k
10 k
100 k
at T (K)
1771
1973
(2227)
(2571)
(3054)
(3779)
Oxidation state s0,[ 4] +1,[ 5] +2, +3 , +4, +5 (a mildly basic oxide) Electronegativity Pauling scale: 1.13 Atomic radius empirical: 182 pm Covalent radius 203±7 pm Spectral line s of ప్రాసియోడిమియంNatural occurrence primordial Crystal structure hexagonal Speed of sound thin rod 2280 m/s (at 20 °C) Thermal expansion (r.t. ) (α, poly) 6.7 µm/(m⋅K) Thermal conductivity 12.5 W/(m⋅K) Electrical resistivity (r.t. ) (α, poly) 0.700 µ Ω⋅m Magnetic ordering paramagnetic [ 6] Young's modulus (α form) 37.3 GPa Shear modulus (α form) 14.8 GPa Bulk modulus (α form) 28.8 GPa Poisson ratio (α form) 0.281 Vickers hardness 400 MPa Brinell hardness 481 MPa CAS Number 7440-10-0 Discovery Carl Auer von Welsbach (1885) Template:infobox ప్రాసియోడిమియం isotopes does not exist Category: ప్రాసియోడిమియం | references
References
These references will appear in the article, but this list appears only on this page.
↑ మూస:OED
↑ "Standard Atomic Weights: Praseodymium" . CIAAW . 2017.
↑ Prohaska, Thomas; Irrgeher, Johanna; Benefield, Jacqueline; et al. (2022-05-04). "Standard atomic weights of the elements 2021 (IUPAC Technical Report)" . Pure and Applied Chemistry (in ఇంగ్లీష్). doi :10.1515/pac-2019-0603 . ISSN 1365-3075 .
↑ Yttrium and all lanthanides except Ce and Pm have been observed in the oxidation state 0 in bis(1,3,5-tri-t-butylbenzene) complexes, see Cloke, F. Geoffrey N. (1993). "Zero Oxidation State Compounds of Scandium, Yttrium, and the Lanthanides". Chem. Soc. Rev . 22 : 17–24. doi :10.1039/CS9932200017 . and Arnold, Polly L.; Petrukhina, Marina A.; Bochenkov, Vladimir E.; Shabatina, Tatyana I.; Zagorskii, Vyacheslav V.; Cloke (2003-12-15). "Arene complexation of Sm, Eu, Tm and Yb atoms: a variable temperature spectroscopic investigation". Journal of Organometallic Chemistry . 688 (1–2): 49–55. doi :10.1016/j.jorganchem.2003.08.028 .
↑ Chen, Xin; et al. (2019-12-13). "Lanthanides with Unusually Low Oxidation States in the PrB3– and PrB4– Boride Clusters". Inorganic Chemistry . 58 (1): 411–418. doi :10.1021/acs.inorgchem.8b02572 . PMID 30543295 . S2CID 56148031 .
↑ M. Jackson "Magnetism of Rare Earth" The IRM quarterly col. 10, No. 3, p. 1, 2000
↑ మూస:OED