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Antimony
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Antimony

tin – antimony – tellurium
As
Sb
Bi  
 
 

General
Name, Symbol, Numberantimony, Sb, 51
Series metalloids
Group, Period, Block15 (VA), 5, p
Density, Hardness 6697 kg/m3, 3
Appearance silvery lustrous grey
Atomic properties
Atomic weight 121.760 amu
Atomic radius (calc.) 145 (133) pm
Covalent radius 138 pm
van der Waals radius no data
Electron configuration [Kr]44d10 5s2 5p3
e- 's per energy level2, 8, 18, 18, 5
Oxidation states (Oxide) ±1 (mildly acidic)
Crystal structure Rhombohedral
Physical properties
State of matter Solid
Melting point 903.78 K (1167.13 °F)
Boiling point 1860 K (2889 °F)
Molar volume 18.19 ×10;10-6 m3/mol
Heat of vaporization 77.14 kJ/mol
Heat of fusion 19.87 kJ/mol
Vapor pressure 2.49 E-9 Pa @ 6304 K
Speed of sound __ m/s at __ K
Miscellaneous
Electronegativity 2.05 (Pauling scale)
Specific heat capacity 210 J/(kg*K)
Electrical conductivity 2.88 106/m ohm
Thermal conductivity 24.3 W/(m*K)
1st ionization potential 834 kJ/mol
2nd ionization potential 1594.9 kJ/mol
3rd ionization potential 2440 kJ/mol
4th ionization potential 4260 kJ/mol
5th ionization potential 5400 kJ/mol
6th ionization potential 10400 kJ/mol
Most stable isotopes
isoNAhalf-life DMDE MeVDP
121Sb57.36%Sb is stable with 70 neutrons
123Sb42.64%Sb is stable with 72 neutrons
125Sb{syn.}2.7582 yBeta-0.767125Te
SI units & STP are used except where noted.

Antimony is a chemical element in the periodic table that has the symbol Sb and atomic number 51. A metalloid, antimony has four allotropic forms. The stable form of antimony is a blue-white metal. Yellow and black antimony are unstable non-metals. Used in flame-proofing, paints, ceramics, enamels, a wide variety of alloys, and rubber.

Table of contents
1 Notable characteristics
2 Applications
3 History
4 Sources
5 Precautions
6 Reference
7 External links

Notable characteristics

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.

Estimates of the abundance of antimony in the Earth's crust range from 0.2 to 0.5 ppm. Antimony is chalcophile, occurring with sulfur and the heavy metals lead, copper, and silver.

Applications

Antimony is increasingly being used in the semiconductor industry in the production of diodes, infrared detectors, and Hall-effect devices. As an alloy, this semi-metal greatly increases lead's hardness and mechanical strength. The most important use of antimony metal is as a hardener in lead for storage batteries. Other uses; Antimony compounds in the form of oxides, sulfides, sodium antimonate, and antimony trichloride are used in the making of flame-proofing compounds, ceramic enamels, glass, paints, 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.

History

Antimony was recognized in antiquity (3000 BC) in various compounds, and it was prized for its fine casting qualities. It was first reported scientifically by Tholden in 1450, and was known to be a metal by the beginning of the 17th century. The origin of the name "antimony" is not clear; the term may come from the Greek words "anti" and "monos", which approximately means "a metal not found alone", or from the Arabian expression "Antos Ammon", which could be translated as "bloom of the god Ammon".

alchemical symbol for the element is shown opposite.
The natural sulfide of antimony, stibnite, was known and used in Biblical times as medicine and as a cosmetic. The relationship between antimony's modern name and its symbol is complex; the Coptic name for the cosmetic powder antimony sulfide was borrowed by the Greeks, which was in turn borrowed by Latin, resulting in stibium. The chemical pioneer Jacob Berzelius used an abbreviation of this name for antimony in his writings, and his usage became the standard symbol. Antimony was until recently used for the treatment of schistosomiasis. Antimony attaches itself to sulfur atoms in certain enzymes which are used both by the parasite and human host. Small doses can kill the parasite without causing damage to the patient.

Sources

Even though this element is not abundant, it is found in over 100 mineral species. Antimony is sometimes found native, but more frequently it is found in the sulfide stibnite (Sb2S3) which is the predominant ore mineral. Commercial forms of antimony are generally ingots, broken pieces, granules, and cast cake. Other forms are powder, shot, and single crystals.

Precautions

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.

Reference

External links