5399. Lead Arsenate

Nomenclature

CAS number: 7784-40-9
Arsenic acid (H3AsO4) lead(2+) salt (1:1); acid lead arsenate; lead hydroarsenate; lead hydrogen arsenate.
HAsO4Pb; mol wt 347.13.
H 0.29%, As 21.58%, O 18.44%, Pb 59.69%.
PbHAsO4.

Description and references

Common form of lead arsenate; occurs in nature as the mineral, schultenite. Prepd by adding excess lead nitrate to a soln of sodium arsenate: H. V. Tartar, R. H. Robinson, J. Am. Chem. Soc. 36, 1843 (1914) DOI; Mellor's Vol. IX, 193 (1929). Insecticidal properties: L. B. Norton, Ind. Eng. Chem. 40, 691 (1948) DOI. Industrial prepn: R. J. Thrift, US 2549945 (1951 to DuPont). Ferroelectric properties: B. B. Lavrencic, J. Petzelt, J. Chem. Phys. 67, 3890 (1977) DOI; N. Kida et al., J. Electron Spectrosc. Relat. Phenom. 101-103, 603 (1999) DOI. Synthesis and characterization of nanocrystals: Z. Xiu et al., Mater. Res. Bull. 39, 2019 (2004) DOI. Analysis and distribution in contaminated soils: K. Newton et al., Environ. Pollut. 143, 197 (2006) DOI PubMed.

Properties

White, heavy powder. Poisonous. d204 5.786. At ≈280° loses H2O and is converted into pyroarsenate. Insol in water. Sol in HNO3, caustic alkalies. LD50 in rats, rabbits (mg/kg): 825, 125 orally; see J. L. Voight et al., J. Am. Pharm. Assoc. Sci. Ed. 37, 122 (1948).

Derivative

Schultenite.

Nomenclature

CAS number: 14758-11-3

Description and references

Description: L. J. Spencer, Nature 118, 411 (1926) DOI; R. Falls et al., Mineral. Mag. 49, 65 (1985) DOI.

Properties

Colorless through white to yellowish, transparent, euhedral crystals with white streak. Hardness: 2.5. Refractive index: 1.9255. d 6.06.

Use

Formerly in insecticidal sprays for fruit orchards.