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Silver
Name; Origin is from the Anglo-Saxon word seolfor.
Chemical symbol; Comes from the Latin word for silver, argentum. Ag
Atomic Number; 47B
Atomic weight; 107.8682
Melting point; 1234.93 K (961.78°C or 1763.20°F)
Boiling point; 2435 K (2162°C or 3924°F)
Density; 10.501 grams per cubic centimetre
Period number; 5
Group Number; 11
Estimated crustal abundance; 7.5×10-2 milligrams per kilogram
Estimated oceanic abundance; 4×10-5 milligrams per litre
Number of stable isotopes; 2
Ionisation energy; 7.576eV
Oxidisation state; 1
Electron shell configuration;
1s2
2s2 2p6
3s2 3p6 3d10
4s2 4p6 4d10
5s1
Archaeological evidence suggests that people have been using silver for at least 5000 years.
Silver can be obtained from pure deposits, from silver ores such as argentite (Ag2S) and horn silver (AgCl),
and in conjunction with deposits of ores containing lead, gold or copper.
Silver and silver compounds have many uses. Pure silver is the best conductor of heat and electricity of all known metals,
so it is sometimes used in making solder, electrical contacts and printed circuit boards. Silver is also the best reflector of
visible light known, but silver mirrors must be given a protective coating to prevent them from tarnishing. Silver has also been
used to create coins, although today other metals are typically used in its place. Sterling silver, an alloy containing 92.5% silver,
is used to make silverware, jewellery and other decorative items. High capacity batteries can be made with silver and zinc and silver
and cadmium. Sliver nitrate (AgNO3) is light sensitive and is used to make photographic films and papers. Silver iodide (AgI) is
used to seed clouds to produce rain.
A major watershed of silver production was the discovery of the New World in 1492, after which time major silver mines in
Mexico, Bolivia, and Peru were opened leading to a rapid rise in the annual world production of silver. This rise, coupled with
improved techniques for extracting silver from ore, broadened both the quality and quantity of ore that could be exploited.
Later improvements, particularly in the late 19th and early 20th centuries, vastly enhanced the base of silver production and
accelerated the exploitation of silver as a by-product of base-metal mining.
Only about 25 percent of cumulative world silver production occurred before the 1770s. Records remain somewhat incomplete
for the periods before 1900, however they play a critical part in determining cumulative historical production.
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