Antimony is a chemical element with the symbol Sb (Latin: stibium, meaning "mark") and atomic number 51. A metalloid, antimony has four allotropic forms. The stable form of antimony is a blue-white metalloid. Yellow and black antimony are unstable non-metals. Antimony is used in flame-proofing, paints, ceramics, enamels, a wide variety of alloys, electronics, and rubber.
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 a metal in its appearance and in many of its 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 are unusual in that they expand on cooling. Antimony is geochemically categorized as a chalcophile, occurring with sulfur and the heavy metals lead, copper, and silver.
Estimates of the abundance of antimony in the Earth's crust range from 0.2 to 0.5 ppm.
Technical Data
Symbol |
Sb |
Density (25°C)/gcm-3 |
6.691 |
Atomic number |
51 |
Melting point / °C |
630.74 |
Atomic weight |
121.75 |
Boiling point / °C |
1587 |
Electronic configuration |
[Kr] 4d105s25p3 |
rcov(MIII single bond)/pm |
140 |
Ionization energy/MJmol-1 I |
0.834 |
rionic(6-coordinate)(MIII)/pm |
76 |
II |
1.595 |
(6-coordinate)(Mv)/pm |
60 |
III |
2.443 |
Hardness (Mohs) |
3.35 |
Sum (I+II+III)/MJmof-1 |
4.872 |
Electrical resistivity (20°C)/μohm cm |
41.7 |
Sum (IV+V)/MJmof -1 |
9.636 |
Contraction on freezing/% |
0.8 |
Electronegativity χ |
1.9 |
|
|
Evaporation Techniques
Temperature (oC) @Vap. Pressure |
Techniques |
Remarks |
10-8 Torr |
10-6 Torr |
10-4 Torr |
Electron Beam |
Crucible |
Coil |
Boat |
279 Sublimes |
345 Sublimes |
425 Sublimes |
Poor |
BN, Graphite & Al2O3 |
Molybdenum & Tantalum |
Molybdenum, Tantalum coated with Al2O3 |
Toxic, evaporates well. Film structure is rate dependent. |