Tin derives its name from the anglo-saxon word ītinī. It derives its chemical symbol īSnī from the latin word stannum. The first uses of tin appear to have been in alloys with copper and zinc to make brass and bronze, and can be dated back to about 3,500 BC. It is not known who identified tin as an element and it may have been recognized as something that could not be divided any further, or was elemental, by alchemists and experimenters.
Tin is a silvery-white metal, is malleable, somewhat ductile, and has a highly crystalline structure. If tin is bent, the breaking of these crystals will emit an audible "tin cry".
Tin does not easily oxidize in air but when heated in air readily forms the tin oxide, SnO2. It resists distilled, sea, and soft tap water, but is attacked by strong acids, alkalis, and acid salts.
Tin is the most tonally resonant of all metals. When a tin/lead alloy cools, the lead cools slightly faster and makes a mottled or spotted effect. This metal alloy is referred to as spotted metal. Tin is obtained chiefly from the minerals cassiterite, a tin oxide, and stannite, a tin sulphide. Both may carry some indium, a rare metal with many opto-electronic applications.
APPLICATIONS OF TIN
Alloyed Materials: Bronze is an alloy of tin and copper, but is mostly copper (12% tin), while addition of phosphorus gives phosphor bronze. Bell metal is also a copper-tin alloy, containing 22% tin. Tin and lead are alloyed to make pewter (85-99% tin). Babbitt metal for bearings has a high percentage of tin as well. Type metal for printing, and fusible metal for fire suppression and electrical safety are other examples of tin alloys.
Glassmaking: Tin is used in the Pilkington process to produce window glass. In the Pilkington process, molten glass is poured onto a pool of molten tin, effectively creating float glass. The glass floats on the surface of the tin and cools, forming solid glass with flat, parallel surfaces. Most of the window glass produced today is made this way.
Solders: Tin has long been used as a solder in the form of an alloy with lead. Tin forms a eutectic mixture with lead containing 63% tin and 37% lead. Such solders are primarily used for solders for joining pipes or electric circuits. Since the European Union Waste Electrical and Electronic Equipment Directive (WEEED) and Restriction of Hazardous Substances Directive (RoHS) came into effect on 1 July 2006, the use of lead in such alloys has decreased.
Other Uses: Tin salts can be sprayed onto glass to make electrically conductive coatings used to make panel lighting and frost-free windshields; Stannous fluoride (SnF2) is used in some types of toothpaste. Most metal pipes in pipe organs are made of varying amounts of tin/lead alloys, with 50% tin and 50% lead being the most common. The amount of tin in an organ pipe defines the pipe's tone.
The niobium-tin compound Nb3Sn is commercially used in wires for superconducting magnets. Superconducting magnets weighing only a couple of kilograms are capable of producing magnetic fields comparable to conventional electromagnet weighing several tonnes.
For chemical and physical properties: www.webelements.com or http://education.jlab.org/itselemental/ele050.html
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