692. Antimony

Nomenclature

CAS number: 7440-36-0
Stibium; regulus of antimony.

Description and references

Sb; at. wt 121.60; at. no. 51; valence 3, 5. Group VA (15). Two naturally occurring isotopes: 121 (57.25%); 123 (42.75%); artificial radioactive isotopes: 112-120; 122; 124-135; isotopes 122 and 124 are useful radioactive tracers. First accurate description of antimony by Thlde (Basil Valentine) in 1604. Antimony ore is mined in China, Mexico, and Bolivia. The antimony of commerce is about 99% pure. Prepn in the laboratory by reduction of Sb2O5 with KCN: Schenk in Handbook of Preparative Inorganic Chemistry vol. 1, G. Brauer, Ed. (Academic Press, New York, 2nd ed., 1963) p 606. Toxicity study: W. R. Bradley, W. G. Fredrick, Ind. Med. 10, Ind. Hyg. Sect. 2, 15 (1941). Review: Smith, “Arsenic, Antimony and Bismuth” in Comprehensive Inorganic Chemistry vol. 2, J. C. Bailar, Jr. et al., Eds. (Pergamon Press, Oxford, 1973) pp 547-683; S. C. Carapella in Kirk-Othmer Encyclopedia of Chemical Technology vol. 3 (Wiley-Interscience, New York, 3rd ed., 1978) pp 96-105. Review of toxicology and human exposure: Toxicological Profile for Antimony and Compounds (PB93-110641, 1992) 160 pp.

Properties

Silver-white, lustrous, hard, brittle metal; scale-like crystalline structure; or dark gray, lustrous powder. Is not tarnished in dry air and only slowly in moist air. d 6.68. mp 630°. bp 1635°; also reported to be 1440°: Gmelins, Antimony (8th ed.) 18B, p 69 (1949). sp heat 0.049; electrical resistivity 39 μ-ohm-cm at 0°. Not affected by cold dil acids; attacked by hot concd H2SO4; readily by aqua regia. Nitric acid, depending on the concn, converts it to antimonous or antimonic oxide. When finely divided it reacts with hot concd HCl. Qualitative analysis for antimony: react with slight excess of HCl with aid of HNO3; pour soln in large vol of water; white ppt forms which becomes orange-red on addn of H2S and is sol in ammonium sulfide. LD50 in rats, guinea pigs (mg Sb/100 g): 10.0, 15.0 i.p. (Bradley, Fredrick).

Caution

Potential symptoms of overexposure are cough, dizziness, headache, nausea, vomiting, diarrhea, stomach cramps, insomnia, anorexia, inability to smell properly. Direct contact may cause irritation of eyes, skin, nose, throat and mouth. See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH 97-140, 2003) p 18.

Use

In manufacture of alloys, such as Britannia or Babbitt metal, hard lead, white metal, type, bullets and bearing metal; in fireworks; for thermoelectric piles, blackening iron, coating metals, etc.