Praseodymium(III) sulfate

Praseodymium(III) sulfate
Names
Praseodymium sulfate octahydrate
IUPAC name praseodymium(3+); trisulfate
Other names Praseodymium sulphate, dipraseodymium trisulphate, praseodymium(III) sulfate
Identifiers
CAS Number	10277-44-8^Y 13510-41-3 (octahydrate)
3D model (JSmol)	Interactive image
ChemSpider	145346^Y
ECHA InfoCard	100.030.553
EC Number	233-622-8
PubChem CID	165851 25022097 (octahydrate)
CompTox Dashboard (EPA)	DTXSID70890652
InChI InChI=1S/3H2O4S.2Pr/c31-5(2,3)4;;/h3(H2,1,2,3,4);;/q;;;2+3/p-6 Key: HWZAHTVZMSRSJE-UHFFFAOYSA-H InChI=1S/3H2O4S.8H2O.2Pr/c31-5(2,3)4;;;;;;;;;;/h3(H2,1,2,3, 4);81H2;;/q;;;;;;;;;;;2*+3/p-6 (octahydrate) Key: IJXLQIGVGZNKP-UHFFFAOYSA-H (octahyrate)
SMILES [O-]S(=O)(=O)[O-].[O-]S(=O)(=O)[O-].[O-]S(=O)(=O)[O-].[Pr+3].[Pr+3] O.O.O.O.O.O.O.O.[O-]S(=O)(=O)[O-].[O-]S(=O)(=O)[O-].[O-]S(=O)(=O)[O-]. [Pr+3].[Pr+3] (octahyrate)
Properties
Chemical formula	Pr₂(SO₄)₃ Pr₂(SO₄)₃·nH₂O, n=2,5,8
Molar mass	570.0031 g/mol 714.12534 g/mol (octahydrate)
Appearance	green crystalline solid
Density	3.72 g/cm³^[1]
Melting point	1,010 °C (1,850 °F; 1,280 K) (decomposes)^[1]
Solubility in water	113.0 g/L (20 °C) 108.8 g/L (25 °C)
Magnetic susceptibility (χ)	+9660·10⁻⁶ cm³/mol
Hazards
GHS labelling:^[2]
Pictograms
Signal word	Warning
Hazard statements	H315, H319, H335
Precautionary statements	P261, P264, P271, P280, P302+P352, P304+P340, P305+P351+P338, P312, P321, P332+P313, P337+P313, P362, P403+P233, P405, P501
Flash point	Non-flammable
Related compounds
Other anions	Praseodymium carbonate Praseodymium chloride
Other cations	Neodymium sulfate
Related compounds	Praseodymium(III) oxide Praseodymium(III) sulfide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is ^YN ?) Infobox references

Chemical compound

Praseodymium(III) sulfate is a praseodymium compound with formula Pr₂(SO₄)₃. It is an odourless whitish-green crystalline compound. The anhydrous substance readily absorbs water forming pentahydrate and octahydrate.^[1]

Properties

Praseodymium sulfate is stable under standard conditions. At elevated temperatures, it gradually loses water and becomes more whitish. Like all rare earth sulfates, its solubility decreases with temperature, a property once used to separate it from other, non-rare earth compounds.

Pentahydrate and octahydrate have monoclinic crystal structures with densities of 3.713 and 2.813 g/cm³, respectively. The octahydrate crystals are optically biaxial, with refractive index components of n_α = 1.5399, n_β = 1.5494 and n_γ = 1.5607.^[1] They belong to the space group C12/c1 (No. 15) and have lattice constants a = 1370.0(2) pm, b = 686.1(1) pm, c = 1845.3(2) pm, β = 102.80(1)° and Z = 4.^[3]

Synthesis

Crystals of octahydrate can be grown from solution obtained by dissolving wet Pr₂O₃ powder with sulfuric acid. This procedure can be optimised by adding a few evaporation/dissolution steps involving organic chemicals.^[3]

References

^ ^a ^b ^c ^d National Research Council (U.S.) (1919). Bulletin of the National Research Council. National Academies. pp. 3–. NAP:12020. Retrieved 14 November 2011.
^ "Dipraseodymium trisulphate". pubchem.ncbi.nlm.nih.gov. Retrieved 27 December 2021.
^ ^a ^b Y.-Q. Zheng, Y.-J. Zhu and J.-L. Lin (2002). "Redeterminaton of the crystal structure of praseodymium sulfate octahydrate, Pr₂(SO₄)₃·8H₂O". Zeitschrift für Kristallographie – New Crystal Structures. 217: 299–300. doi:10.1524/ncrs.2002.217.jg.299. S2CID 201278521. PDF copy