Neodymium arsenate

Neodymium arsenate, also known as neodymium(III) arsenate, is the arsenate of neodymium with the chemical formula of NdAsO₄. In this compound, neodymium exhibits the +3 oxidation state. It has good thermal stability, and its pK_sp,c is 21.86±0.11.^[2]

Neodymium arsenate

Names
Other names Neodymium(III) arsenate
Identifiers
CAS Number	15479-84-2 Y
3D model (JSmol)	Interactive image
InChI InChI=1S/AsH3O4.Nd/c2-1(3,4)5;/h(H3,2,3,4,5);/q;+3/p-3 Key: NDJXBXBULAKKIO-UHFFFAOYSA-K
SMILES [O-][As](=O)([O-])[O-].[Nd+3]
Properties
Chemical formula	NdAsO4
Molar mass	313.89
Appearance	faint pink powder
Density	5.3-5.9 g/cm3[1]
Solubility in water	insoluble
Hazards
GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H300, H314, H350, H410
Precautionary statements	P201, P264, P273, P280, P305+P351+P338, P310
Related compounds
Other anions	Neodymium(III) nitrate Neodymium(III) phosphate Neodymium(III) antimonate Neodymium(III) bismuthate Neodymium(III) carbonate
Other cations	PrAsO4
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Preparation

Neodymium arsenate can be obtained from the reaction between sodium arsenate (Na₃AsO₄) and neodymium chloride (NdCl₃) in solution:^[3]

Na₃AsO₄ + NdCl₃ → 3 NaCl + NdAsO₄↓

When crystallizing from a lead pyroarsenate flux, neodymium arsenate crystals produced explode when cooled.^[4]

Neodymium arsenate also occurs in nature as a mineral.^[5]

See also

• Arsenic

References

1. Donnay, Joseph Désiré Hubert (1973). Crystal Data: Inorganic compounds. National Bureau of Standards. p. M71.
2. Firsching, F. Henry. (1992). "Solubility products of the trivalent rare-earth arsenates". Journal of Chemical and Engineering Data. 37 (4): 497–499. doi:10.1021/je00008a028.
3. Gabisoniya, Ts. D.; Nanobashvili, E. M.. Synthesis of rare earth metal arsenates. Soobshcheniya Akademii Nauk Gruzinskoi SSR (1980), 97(2), 345-8. ISSN 0002-3167
4. Feigelson, Robert S. (August 1967). "Crystal Growth of Rare-Earth Orthoarsenates". Journal of the American Ceramic Society. 50 (8): 433–434. doi:10.1111/j.1151-2916.1967.tb15150.x.
5. "New Mineral Names". American Mineralogist. 85: 1321–1325. 2000.