Silver

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					Silver
                                History
As Silver has been known of since ancient times, nobody has been credited
with finding it. It has been dated back to 4000BC as ornaments and
decorations found in ancient Egyptian tombs. Archaeologists have concluded
that it is highly likely that silver was used as a form of money in ancient Egypt
at around 800BC.
Many European cultures believed that Silver could be used against mythical
creatures such as the werewolf. A werewolf could be only be killed with a silver
bullet.
The English pound came from the value of a pound of silver, as that was the
unit of trade.
                                   Uses
Because of its attractive and shiny appearance, Silver is made into jewellery
such as earrings, necklaces, bracelets etc.

As silver is a good conductor of electricity, it is sometimes used for electrical
contacts, however because of the availability and price of silver, other metals
are usually used instead.

Silver is also used in photography film, as well as mirrors.

Used as a catalyst to convert ethylene to ethylene oxide.

C2H4 + 1/2O2 --> C2H4O
Silver carbonate (Ag2CO3) is used to remove Carbon dioxide from the air.

Silver chloride (AgCl) can be made transparent and is used as a cement for
glass.

Silver chloride (AgCl) is a widely used electrode for pH testing and
potentiometric measurement.

Silver fulminate (AgONC) is a powerful explosive.

Silver iodide (AgI) has been used in attempts to seed clouds to produce rain.

Silver nitrate (AgNO3) is used as an antiseptic and in some chemical reactions.

Silver sulfide (Ag2S), also known as Silver Whiskers, is formed when silver
electrical contacts are used in an atmosphere rich in hydrogen sulfide.

Silver oxide (Ag2O) is used as a positive electrode (cathode) in watch
batteries.

                       http://en.wikipedia.org/wiki/Silver
                 Physical Properties
- Has a shiny surface.
- Best electrical conductor out of all the metals.
- Not very reactive.
- Best thermal conductor out of the metals.
- Metal with the “whitest” appearance.
                Chemical Properties
Atomic number 47
Atomic mass 107.87 g.mol -1
Density 10.5 g.cm-3 at 20°C
Melting point 962 °C
Boiling point 2212 °C


Natural silver consists of a mixture of two stable isotopes: silver-107 and silver-109


          http://www.lenntech.com/Periodic-chart-elements/Ag-en.htm

				
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