Antimony

Atomic Number:

51

Melting Point: 630.63 ºC
Atomic Symbol: Sb Boiling Point:  1587 ºC
Atomic Weight: 121.75 amu Density: 6697 kg/m 3
Atomic Radius:

142 pm

Oxidation States: 5, 3, -3
Covalent Radius: 138 pm Electron Configuration: [Kr]5s24d105p3
van der Waals Radius:

--

State of Matter: solid

History

(Gr. anti plus monos - "a metal not found alone") It was first reported scientifically by Tholden in 1450. Antimony was recognized in compounds by the ancients and was known as a metal at the beginning of the 17th century and possibly much earlier.

Properties

Antimony in its elemental form is a silvery white, brittle, fusible, crystalline solid that exhibits poor electrical and heat conductivity properties and vaporizes at low temperatures. A metalloid, antimony, resembles metal in its appearance and physical properties, but does not chemically react as a metal. It is also attacked by oxidizing acids and halogens. Antimony and some of its alloys expand on cooling.

Sources

Antimony is not abundant, but is found in over 100 mineral species. It is sometimes found natively, but more frequently it is found as the sulfide stibnite.

Uses

Antimony is finding use in semiconductor technology for making infrared detectors, diodes and Hall-effect devices. It greatly increases the hardness and mechanical strength of lead. Batteries, antifriction alloys, type metal, small arms and tracer bullets, cable sheathing, and minor products use about half the metal produced. Compounds taking up the other half are oxides, sulfides, sodium antimonate, and antimony trichloride. These are used in manufacturing flame-proofing compounds, paints ceramic enamels, glass, and pottery. Antimony trioxide is the most important of the antimony compounds and is primarily used in flame-retardant formulations. These flame-retardant applications include such markets as children's clothing, toys, aircraft and automobile seat covers.

Isotopes

Antimony has several key isotopes ranging in half-lifes from 15.89 minutes to 2.75 years.

Hazards

Antimony and many of its compounds are toxic. Clinically, antimony poisoning is very similar to arsenic poisoning. In small doses, antimony causes headache, dizziness and depression. Larger doses cause violent and frequent vomiting, and will lead to death in few days.