Characteristics Occurrence Allotropes Applications

Compounds Isotopes Precautions Tin Data Interactive Periodic Table

Alchemical Symbol, Tin/Jupiter

Characteristics

Tin is a malleable, ductile, highly crystalline, silvery-white metal; when a bar of tin is bent, a strange crackling sound known as the "tin cry" can be heard due to the breaking of the crystals.  This metal resists corrosion from distilled, sea and soft tap water, but can be attacked by strong acids, alkalis, and by acid salts.  Tin acts as a catalyst when Oxygen is in solution and helps accelerate chemical attack.   It has the look of freshly cut aluminum but the feel of lead.  Polished tin is slightly bluish.

1s² 2s²p⁶ 3s²p⁶d¹⁰ 4s²p⁶d¹⁰ 5s²p²

Tin forms the Dioxide SnO₂ when it is heated in the presence of air.   SnO₂, in turn, is feebly acidic and forms Stannate (SnO₃^-2) salts with basic Oxides.  Tin can be highly polished and is used as a protective coat for other metals in order to prevent corrosion or other chemical action.  This metal combines directly with Chlorine and Oxygen and displaces Hydrogen from dilute acids.   Tin is malleable at ordinary temperatures but is brittle when it is heated.

Additional Representations of Alchemical Symbols for Tin

Occurrence

About 35 countries mine tin throughout the world. Nearly every continent has an important tin-mining country. Tin is produced by reducing the ore with coal in a reverberatory furnace.  This metal is a relatively scarce element with an abundance in the Earth's crust of about 2 ppm, compared with 94 ppm for zinc, 63 ppm for copper, and 12 ppm for lead. Most of the world's tin is produced from placer deposits; at least one-half comes from Southeast Asia.  The only mineral of commercial importance as a source of tin is Cassiterite, SnO₂, although small quantities of tin are recovered from complex Sulfides such as Stannite, Cylindrite, Franckeite, Canfieldite, and Teallite.  Secondary, or scrap, tin is also an important source of the metal.

Tasmania hosts some important deposits of historical importance, most importantly Mount Bischoff and Renison Bell.

Allotropes

Chemically tin shows properties intermediate between those of metals and non-metals, such as the semiconductors Silicon and Germanium.  Tin has two allotropes at normal pressure and temperature, gray Tin, and white Tin.

Below 13.2°C it exists as gray or alpha Tin, which has a cubic crystal structure similar to Silicon and Germanium.  Gray Tin has no metallic properties at all, is a dull-gray powdery material, and has no known uses.

When warmed above 13.2°C Tin changes into white or beta Tin, which is metallic and has a tetragonal structure.  Converting gray Tin powder into white Tin produces white Tin powder.  To convert powdery gray Tin into solid white Tin the temperature must be raised above the melting point of Tin.

Gray Tin can be a real problem, since metallic white Tin will slowly convert to gray Tin if it is held for a long time below 13.2°Celsius.  The metallic surface of white Tin becomes covered with a gray powder which is easily rubbed off.  The gray patches slowly expand until all of the Tin in the object is converted from the metal to the powder, at which point it totally loses its structural integrity and falls to pieces.  This process is known as Tin Disease or Tin Pest.  Tin Pest was a particular problem in northern Europe in the 18th century as organ pipes made of Tin would sometimes completely disintegrate during long cold winters.  The transformation can be prevented by the addition of Antimony or Bismuth.

Applications

Perhaps one of the most familiar of tin compounds, SnF₂, Tin (II) Fluoride, goes by the trade name of fluoristan and is found in some fluoride toothpastes.   Tin bonds readily to Iron, and has been used for coating Lead or Zinc and steel to prevent corrosion.  Tin-plated steel containers are widely used for food preservation, and this forms a large part of the market for metallic Tin.  Speakers of British English call them "Tins"; Americans call them "Tin Cans".   One thus-derived use of the slang term "tinnie" or "tinny" means "can of beer".  The Tin Whistle is so called because it was first mass-produced in tin-plated steel.

• Some important tin alloys are: bronze, bell metal, Babbitt metal, die casting alloy, pewter, phosphor bronze, soft solder, and White metal.
• The most important salt formed is Stannous Chloride, which has found use as a reducing agent and as a mordant in the calico printing process.  Electrically conductive coatings are produced when tin salts are sprayed onto glass.  These coatings have been used in panel lighting and in the production of frost-free windshields. 
• Most metal pipes in a pipe organ are made of varying amounts of a tin/lead alloy, with 50%/50% being the most common.  The amount of tin in the pipe defines the pipe's tone, since 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.
• Window glass is most often made via floating molten glass on top of molten tin (creating float glass) in order to make a flat surface (this is called the "Pilkington Process"). 
• Tin is also used in solders for joining pipes or electric circuits, in bearing alloys, in glass-making, and in a wide range of tin chemical applications. Although of higher melting point than a Lead-Tin alloy, the use of pure tin or tin alloyed with other metals in these applications is rapidly supplanting the use of the previously common lead–containing alloys in order to eliminate the problems of toxicity caused by lead.
• Tin foil was once a common wrapping material for foods and drugs; replaced in the early 20th century by the use of aluminum foil, which is now commonly referred to as tin foil. Hence one use of the slang term "tinnie" or "tinny" for a small retail package of a drug such as Cannabis or for a can of beer.

Tin becomes a superconductor below 3.72^oK.  In fact, tin was one of the first superconductors to be studied; the Meissner Effect, one of the characteristic features of superconductors, was first discovered in superconducting tin crystals. The Niobium-Tin compound Nb₃Sn is commercially used as wires for superconducting magnets, due to the material's high critical temperature (18^oK) and critical magnetic field (25T).  A superconducting magnet weighing only a couple of kilograms is capable of producing magnetic fields comparable to a conventional electromagnet weighing tons.

Compounds

Tin  also forms Stannate (SnO₃^2-) and Stannite (SnO₂^-) compounds.

Alchemical Symbol, Tin

Isotopes

Tin is the element with the greatest number of stable isotopes, 10, which is probably related to the fact that 50 is a "magic number" of protons.  28 additional unstable isotopes are known, including the "doubly magic tin-100 (¹⁰⁰Sn) (discovered in 1994).

Precautions

The small amount of Tin that is found in canned foods is not harmful to humans. Certain organic Tin compounds, Organotin, such as triorganotins are toxic and are used as industrial fungicides and bactericides.

(anglo-Saxon, tin; L. stannum) Known to the ancients. Tin is found chiefly in cassiterite (SnO₂). Most of the world's supply comes from Malaya, Bolivia, Indonesia, Zaire, Thailand, and Nigeria. The U.S. produces almost none, although occurrences have been found in Alaska and California. Tin is obtained by reducing the ore with coal in a reverberatory furnace. Ordinary tin is composed of nine stable isotopes; 18 unstable isotopes are also known. Ordinary tin is a silver-white metal, is malleable, somewhat ductile, and has a highly crystalline structure. Due to the breaking of these crystals, a "tin cry" is heard when a bar is bent. The element has two allotropic forms at normal pressure. On warming, gray, or alpha tin, with a cubic structure, changes at 13.2^oC into white, or beta tin, the ordinary form of the metal. White tin has a tetragonal structure. When tin is cooled below 13.2^oC, it changes slowly from white to gray. This change is affected by impurities such as aluminum and zinc, and can be prevented by small additions of antimony or bismuth. This change from the alpha to beta form is called the tin pest. There are few if any uses for gray tin. Tin takes a high polish and is used to coat other metals to prevent corrosion or other chemical action. Such tin plate over steel is used in the so-called tin can for preserving food. Alloys of tin are very important. Soft solder, type metal, fusible metal, pewter, bronze, bell metal, Babbitt metal, White metal, die casting alloy, and phosphor bronze are some of the important alloys using tin. Tin resists distilled sea and soft tap water, but is attacked by strong acids, alkalis, and acid salts. Oxygen in solution accelerates the attack. When heated in air, tin forms SnO₂, which is feebly acid, forming stannate salts with basic oxides. The most important salt is the chloride, which is used as a reducing agent and as a mordant in calico printing. Tin salts sprayed onto glass are used to produce electrically conductive coatings. These have been used for panel lighting and for frost-free windshields. Most window glass is now made by floating molten glass on molten tin (float glass) to produce a flat surface (Pilkington process). Of recent interest is a crystalline tin-niobium alloy that is superconductive at very low temperatures. This promises to be important in the construction of superconductive magnets that generate enormous field strengths but use practically no power. Such magnets, made of tin-niobium wire, weigh but a few pounds and produce magnetic fields that, when started with a small battery, are comparable to that of a 100 ton electromagnet operated continuously with a large power supply. The small amount of tin found in canned foods is quite harmless. The agreed limit of tin content in U.S. foods is 300 mg/kg. The trialkyl and triaryl tin compounds are used as biocides and must be handled carefully. Over the past 25 years the price of tin has varied from 50 cents/lb to its present price of about $4/lb. as of January 1990.

Source: CRC Handbook of Chemistry and Physics, 1913-1995. David R. Lide, Editor in Chief. Author: C.R. Hammond

Archaeological evidence suggests that people have been using Tin for at least 5500 years.  Tin is primarily obtained from the mineral Cassiterite (SnO₂) and is extracted by roasting Cassiterite in a furnace with Carbon.  Tin makes up only about 0.001% of the earth's crust and is chiefly mined in Malaysia.

Two allotropes of tin occur near room temperature. The first form of Tin is called Gray Tin and is stable at temperatures below 13.2°C (55.76°F).  There are few, if any, uses for Gray Tin.  At temperatures above 13.2°C, Gray Tin slowly turns into tin's second form, White Tin.  White Tin is the normal form of the metal and has many uses.  Unfortunately, White Tin will turn into Gray Tin if its temperature falls below 13.2°C.  This change can be prevented if small amounts of Antimony or Bismuth are added to White Tin.

Tin resists corrosion and is used as a protective coating on other metals.  Tin cans are probably the most familiar example of this application.  A Tin can is actually made from steel.  A thin layer of Tin is applied to the inside and outside of the can to keep the steel from rusting.  Once widely used, Tin cans have largely been replaced with plastic and Aluminum containers.

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.  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.

Tin is used to form many useful alloys.  Bronze is an alloy of Tin and Copper.  Tin and Lead are alloyed to make pewter and solder.  An alloy of Tin and Niobium is used to make superconductive wire.  Type metal, fusible metal, bell metal and Babbitt metal are other examples of Tin alloys.

Tin salts can be sprayed onto glass to make electrically conductive coatings.  These can then be used to make panel lighting and frost-free windshields.   Stannous Fluoride (SnF₂) is used in some types of toothpaste.