Praseodymium(III) selenate

Praseodymium(III) selenate

Names
Other names Praseodymium(III) selenate(VI)
Identifiers
3D model (JSmol)	Interactive image
ChemSpider	15008002
PubChem CID	15801702
InChI InChI=1S/3H2O4Se.2Pr/c3*1-5(2,3)4;;/h3*(H2,1,2,3,4);;/q;;;2*+3/p-6 Key: RAKZQMKNASWERS-UHFFFAOYSA-H
SMILES [O-][Se](=O)(=O)[O-].[O-][Se](=O)(=O)[O-].[O-][Se](=O)(=O)[O-].[Pr+3].[Pr+3]
Properties
Chemical formula	Pr2(SeO4)3
Molar mass	710.6868 g/mol (anhydrous) 782.74792 g/mol (tetrahydrate) 800.7632 g/mol (pentahydrate) 836.79376 g/mol (heptahydrate) 854.80904 g/mol (octahydrate) 926.87016 g/mol (dodecahydrate)
Appearance	pale green crystals (heptahydrate)[1]
Density	4.3 g/cm^3 (anhydrous) 3.85 g/cm^3 (tetrahydrate)[2] 3.094 g/cm^3 (octahydrate)
Solubility in water	36 g/100 mL (0 °C) 3 g/100 mL (92 °C)
Related compounds
Other anions	Praseodymium(III) sulfate
Other cations	Cerium(III) selenate Neodymium(III) selenate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Praseodymium(III) selenate is an inorganic compound, the salt of praseodymium and selenic acid with the chemical formula Pr₂(SeO₄)₃. It forms green crystals when hydrated.

Preparation

Praseodymium(III) selenate can be obtained by dissolving praseodymium(III) oxide in a solution of selenic acid:^[3]

Pr₂O₃ + 3 H₂SeO₄ → Pr₂(SeO₄)₃ + 3 H₂O

Properties

Praseodymium(III) selenate dissolves in water, and forms green crystals when hydrated. These crystals are of Pr₂(SeO₄)₃·nH₂O, where n = 4, 5, 7, 8 and 12. During crystallization from cold solutions, the octahydrate is formed, and the pentahydrate can be formed from hot solutions.

With potassium selenate and many other selenate salts, it forms double salts such as Pr₂(SeO₄)₃·nK₂SeO₄·4H₂O (n = 1 and 3).

References

1. Sc, Y, La-Lu Rare Earth Elements: C 9 Compounds with Se. Springer Science & Business Media. 2013-11-11. p. 455. ISBN 978-3-662-06345-3.
2. Villars, Pierre; Cenzual, Karin; Gladyshevskii, Roman (2013-12-18). Handbook. Walter de Gruyter GmbH & Co KG. p. 1105. ISBN 978-3-11-029444-6.
3. Friend, J. Newton (1932). "352. The solubility of praseodymium selenate in water". Journal of the Chemical Society (Resumed): 2410–2413. doi:10.1039/jr9320002410. ISSN 0368-1769.