Wikijunior:The Elements/Tin





General: Tin is a chemical element. Tin belongs to the carbon family of elements on the periodic table. The Periodic Pable arranges the chemical elements into rows (periods) and columns (groups). Chemical elements are represented by symbols. The symbol for tin is Sn, an abbreviation for the Latin word stannum.

What does it look, feel, taste, and smell like?
Tin is silvery-white in color. It has a slightly bluish tinge. Since it is a metal, tin can be polished and made shiny. Tin contains clear particles called crystals.

Tin feels cool to the touch. It is flexible and bends easily. It is soft and can be cut with little effort. Tin is ductile, meaning it can be drawn out into fine strands. Tin is malleable, meaning it can be molded into various shapes. It can be extruded (pulled) into long tubes. It can be hammered or pressed flat by rollers.

Tin has a metallic taste and is odorless.

Other properties.

1.    Solid tin will melt at about 450 degrees Fahrenheit. This is called the melting point.

2.    Tin easily adheres (sticks) to iron, steel, and copper.

3.    When tin is bent or twisted, the crystals inside crush together to make a cracking sound. This is called a “tin cry”.

4.   Tin has two different forms, white and grey. These different forms are called allotropes. The familiar form is white tin (beta). The less familiar form is

gray tin (alpha). Gray Tin is powdery and of little use. Gray tin changes to white tin when the temperature is above 55.76 degrees Fahrenheit.

Is it dangerous?
Exposure to harmful tin compounds can cause eye and skin irritations, dizziness, and sickness. Such compounds are used for making paint, plastic, fungicides, and pesticides. Some tin compounds are toxic (poisonous).

Pure tin is nontoxic and safe to handle. Food packaged in tin-plated containers has small, harmless amounts of dissolved tin. Metallic Tin and fumes from tin refining are not toxic.

Where does its name come from?
The English word tin comes from the Anglo-Saxon language. The German word for tin is tin-om. The Latin word for tin is stannum, which means alloy (mixture) of silver and lead. The earlier Latin word for tin was plumbum candidum, which means "white lead".

How was it discovered?
How tin was discovered in ancient times is unknown. Some areas of southwest Britain were not covered by ice during the Ice Age. Tin ore was on the surface in regions that were free of ice. In Brittany, France, and the Iberian Peninsula, tin mines date back 4000 years. Tin played a key role in shaping ancient civilizations.

Where is it found?
There is evidence that the Inca and Aztec people mined tin in South and Central America.

Tin mining took place in the Ore Mountains in Europe about 4500 years ago. These ancient mines were located on the border between modern day Germany and the Czech Republic. There were tin mines in Brittany, Devon, Cornwell, and the Iberian Peninsula around 2000 BC.

Much of the tin used by early Mediterranean peoples likely came from the English Isles of Scilly and the Cornish Peninsula.

Tin mines in Yunnan began around 2700 years ago. They eventually became China’s main source of tin.

Later, tin mining developed in other regions of the world. Including Africa, Australia, and the Americas.

Important areas where tin is mined in modern times include:

1. The SE Asian tin belt (Myanmar, Thailand, Malaysia, Indonesia).

2. The South China tin belt.

3. The Central Andean tin belt (Bolivia and southernmost Peru).

4. The Cornwall tin province in southwestern England.

Tin is found in Alaska and other areas in the United States, but there are no more active tin mines. The United States has not produced tin since 1993. As of 2017, tin has become a “critical strategic metal”. This means it is needed for technology and industry but is in short supply. There are no known alternatives. The United States receives much of its tin supply from South America. Recycling plays an important role in maintaining the tin supply. Several processes have been developed for reclaiming tin from scrap tin or tin-plated articles.

What are its uses?
Tin and tin compounds are widely used for:

1.    Reducing friction in moving parts of machines, such as bearings.

2.    Making toothpaste, perfume, polymers and dyes, and lithium batteries.

3.    Plating (coating) steel cans used as food containers.

4.    Soldering (joining) 2 pieces of metal together, mainly for electrical and plumbing work.

5.   Grey tin is sometimes used in semi-conductor applications.

6.   Making alloys such as bronze, pewter, and solder. Because pure tin is relatively weak, it must be mixed with other metals to form alloys. The world’s

first alloy was discovered more than 5,000 years ago. People found that mixing tin and copper produced a hard and durable metal. It could be shaped

into blades which would keep a sharp edge.