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Silver Silver (Ag), chemical element, a white lustrous metal valued for its decorative beauty and electrical conductivity. Silver is located in Group 11 (Ib) and Period 5 of the periodic table, between copper (Period 4) and gold (Period 6), and its physical and chemical properties are intermediate between those two metals. Properties, uses, and occurrence - Together with gold and the platinum-group metals, silver is one of the so -called precious metals. Because of its comparative scarcity, brilliant white colour, malleability, ductility, and resistance to atmospheric oxidation, silver has long been used in the manufacture of coins, ornaments, and jewelry. Silver is one of the noblest—that is, least chemically reactive—of the transition elements.
Silver ornaments and decorations have been found in royal tombs dating back as far as 4000 BCE. It is probable that both gold and silver were used as money by 800 BCE in all countries between the Indus and the Nile. Silver is widely distributed in nature, but the total amount is quite small when compared with other metals; the metal constitutes 0.05 part per million of Earth’s crust. Practically all sulfides of lead, copper, and zinc contain some silver. Silver-bearing ores may contain amounts of silver from a trace to several thousand troy ounces per avoirdupois ton, or about 10 percent. Silver is widely distributed in nature, but the total amount is quite small when compared with other metals; the metal constitutes 0.05 part per million of Earth’s crust. Practically all sulfides of lead, copper, and zinc contain some silver. Silver-bearing ores may contain amounts of silver from a trace to several thousand troy ounces per avoirdupois ton, or about 10 percent. Unlike gold, silver is present in many naturally occurring minerals. Silver is found generally in lead ores, copper ores, and cobalt arsenide ores and is also frequently associated with gold in nature. Most silver is derived as a by-product from ores that are mined and processed to obtain these other metals. Deposits of native (chemically free, or uncombined) silver are also commercially important. Unlike gold, silver is present in many naturally occurring minerals. Silver is found generally in lead ores, copper ores, and cobalt arsenide ores and is also frequently associated with gold in nature. Most silver is derived as a by-product from ores that are mined and processed to obtain these other metals. Deposits of native (chemically free, or uncombined) silver are also commercially important. - Historically, a major use of silver has been monetary, in the form of reserves of silver bullion and in coins. By the 1960s, however, the demand for silver for industrial purposes, in particular the photographic industry, exceeded the total annual world production. In the early 21st century, digital cameras supplanted those that used film, but demand for silver from other sectors—such as for sterling and plated silverware, ornaments, jewelry, coinage, electronic components, and photovoltaic cells—continued to be important.
Historically, a major use of silver has been monetary, in the form of reserves of silver bullion and in coins. By the 1960s, however, the demand for silver for industrial purposes, in particular the photographic industry, exceeded the total annual world production. In the early 21st century, digital cameras supplanted those that used film, but demand for silver from other sectors—such as for sterling and plated silverware, ornaments, jewelry, coinage, electronic components, and photovoltaic cells—continued to be important. Historically, a major use of silver has been monetary, in the form of reserves of silver bullion and in coins. By the 1960s, however, the demand for silver for industrial purposes, in particular the photographic industry, exceeded the total annual world production. In the early 21st century, digital cameras supplanted those that used film, but demand for silver from other sectors—such as for sterling and plated silverware, ornaments, jewelry, coinage, electronic components, and photovoltaic cells—continued to be important. Compounds For silver the preeminently important oxidation state in all of its ordinary chemistry is the state +1, although the states +2 and +3 are known. - Silver compounds include silver chloride (AgCl), silver bromide (AgBr), and silver iodide (AgI). Each of these salts is used in photography. Silver chloride serves as the light-sensitive material in photographic printing papers and, together with silver bromide, in certain films and plates. The iodide is also used in the manufacture of photographic papers and films, as well as in cloud seeding for artificial rainmaking and in some antiseptics. All three halides are derived from silver nitrate (AgNO3), which is the most important of the inorganic silver salts. Besides these other salts, silver nitrate is also the starting material for the production of the silver cyanide used in silver plating.
AgNO3 AgNO3 AgBr
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