All practice pages/Interatomic theory/Elements
Element 51, a metalloid
A brittle metalloid once ground into ancient eyeliner, now mostly used to keep plastics and fabrics from catching fire.
Period 5, group 15. The other metalloids are tinted, and every cell opens its own article.
Five valence electrons, like nitrogen and phosphorus. Antimony mostly shares electrons in covalent bonds, in the +3 or +5 state with oxygen, sulfur and chlorine.
Mined mainly as stibnite (Sb₂S₃), with China, Tajikistan and Russia supplying most of it.
Stibnite was ground into kohl, a black eye cosmetic, in ancient Egypt, and objects of antimony metal survive from the ancient world. Vannoccio Biringuccio described extracting the metal in 1540. The origin of the name is uncertain; the symbol Sb comes from its Latin name stibium.
Antimony trioxide makes flame retardants in plastics, textiles and electronics work better, and takes the largest share. Antimony hardens the lead in car batteries and bullets, and it goes into semiconductors, glass and the catalysts used to make PET plastic bottles.
Antimony and many of its compounds are toxic, in ways similar to arsenic but milder.