Atomic number ............ 51
Atomic mass ........... 121.75 g.mol -1
Density .................... 6.684 g.cm-3
Melting point ..... 631 °C
Boiling point .... 1380 °C.....
Discovered by The ancientsProgram Created By richard orberson 11/28/2113
Antimony si a semimetallic chemical element which can exist in two forms: the metallic form is bright, silvery, hard and brittle; the non metallic form is a grey powder. Antimony is a poor conductor of heat and electricity, it is stable in dry air and is not attacked by dilute acids or alkalis. Antimony and some of its alloys expand on cooling.
Antimony has been known since ancient times. It is sometimes found free in nature, but is usually obtained from the ores stibnite (Sb2S3) and valentinite (Sb2O3). Nicolas Lémery, a French chemist, was the first person to scientifically study antimony and its compounds. He published his findings in 1707. Antimony makes up about 0.00002% of the earth's crust.
Very pure antimony is used to make certain types of semiconductor devices, such as diodes and infrared detectors. Antimony is alloyed with lead to increase lead's durability. Antimony alloys are also used in batteries, low friction metals, type metal and cable sheathing, among other products. Antimony compounds are used to make flame-proofing materials, paints, ceramic enamels, glass and pottery. The ancient Egyptians used antimony, in the form of stibnite, for black eye make-up.
Antimony occurs naturally in the environment. But it also enters the environment through several applications by humans. Antimony is an important metal in the world economy. Annual production is about 50.000 tonnes per year, with virgin materials coming mainly from china, Russia, Bolivia and South Africa. World reserves exceed 5 million tonnes. In Finland there is a deposit of elemental antimony.
Especially people that work with antimony can suffer the effects of exposure by breathing in antimony dusts. Human exposure to antimony can take place by breathing air, drinking water and eating foods that contain it, but also by skin contact with soil, water and other substances that contain it. Breathing in antimony that is bond to hydrogen in the gaseous phase, is what mainly causes the health effects.
Exposure to relatively high concentrations of antimony (9 mg/m3 of air) for a longer period of time can cause irritation of the eyes, skin and lungs. As the exposure continues more serious health effects may occur, such as lung diseases, heart problems, diarrhea, severe vomiting and stomach ulcers. It is not known whether antimony can cause cancer or reproductive failure.
Antimony is used as a medine for parasital infections, but people who have had too much of the medicine or were sensitive to it have experienced health effects in the past. These health effects have made us more aware of the dangers of exposure to antimony.
Antimony can be found in soils, waters and air in very small amounts. Antimony will mainly pollute soils. Through groundwater it can travel great distances towards other locations and surface waters.
Laboratory tests with rats, rabbits and guinea pigs have shown us that relatively high levels of antimony may kill small animals. Rats may experience lung, heart, liver and kidney damage prior to death.
Animals that breathe in low levels of antimony for a long time may experience eye irritation, hair loss and lung damage. Dogs may experience heart problems even when they are exposed to low levels of antimony. Animals that breathed in low levels of antimony for a couple of months may also experience fertility problems.
Whether antimony can cause cancer has not been fully specified yet.