Tin (Stannum), Sn - chemical main group element of group IV of the periodic system of elements of D. I. Mendeleyev. Ever since. room 50, at. mass (ATA. weight) 118,69, valence +2, +4. Known 10 stable and 20 of radioactive isotopes. Occurs in native state and connections. Widely distributed in nature. The man tin found in all tissues and organs, richer bones, liver, lungs and kidneys.
Tin - soft, malleable, silvery-white metal, density 7,28, temperature PL 231,91 degrees. At temperatures below 13o O. turns into a powder of grey color ("tin plague"), Acting reacts with acids, alkalis, Halogens, sulfur and others With oxygen to form carbon monoxide tin oxide and dioxide SnO2; these oxides hydroxides Sn(OH)2 and Sn(HE)4 have amphoteric properties, with alkalis to form a salt tin acids - stannite, for example Na[Sn(OH)3], and stannate, for example Na2SnO3·3H2O. Practical importance sulfide SnS2 (gold) and chlorides SnCl2·2H2O and SnCl4. All connections bivalent tin - strong reducing agents. Apply tin for manufacturing staniolja, tinplate, various alloys. Connection O. used in the dyeing of cloths, the production of enamels, glazes, milk glass, in analytical chemistry, etc.
In medicine drugs tin currently rarely used. From compounds Acting significant toxicity have hydride SnH4 - severe convulsive poison and organic compounds Acting causing the defeat of the Central nervous system Displays the Acting from the body mainly with faeces.