Silver

Jai Ganesh · 2025-08-09 16:33:23

Silver

Gist

Silver, denoted by the symbol Ag and atomic number 47, is a lustrous, soft, and highly conductive metal. It is known for its exceptional electrical and thermal conductivity, as well as its high reflectivity.

Silver, with the symbol Ag and atomic number 47, is a soft, white, lustrous transition metal known for its exceptional electrical and thermal conductivity, and reflectivity. It's a precious metal, often found in jewelry, coins, and decorative items, but also plays a vital role in various industrial and technological applications.

Summary

Silver is a chemical element; it has symbol Ag (from Latin argentum 'silver') and atomic number 47. A soft, whitish-gray, lustrous transition metal, it exhibits the highest electrical conductivity, thermal conductivity, and reflectivity of any metal. Silver is found in the Earth's crust in the pure, free elemental form ("native silver"), as an alloy with gold and other metals, and in minerals such as argentite and chlorargyrite. Most silver is produced as a byproduct of copper, gold, lead, and zinc refining.

Silver has long been valued as a precious metal, commonly sold and marketed beside gold and platinum. Silver metal is used in many bullion coins, sometimes alongside gold: while it is more abundant than gold, it is much less abundant as a native metal. Its purity is typically measured on a per-mille basis; a 94%-pure alloy is described as "0.940 fine". As one of the seven metals of antiquity, silver has had an enduring role in most human cultures. In terms of scarcity, silver is the most abundant of the big three precious metals—platinum, gold, and silver—among these, platinum is the rarest with around 139 troy ounces of silver mined for every one ounce of platinum.

Other than in currency and as an investment medium (coins and bullion), silver is used in solar panels, water filtration, jewellery, ornaments, high-value tableware and utensils (hence the term "silverware"), in electrical contacts and conductors, in specialised mirrors, window coatings, in catalysis of chemical reactions, as a colorant in stained glass, and in specialised confectionery. Its compounds are used in photographic and X-ray film. Dilute solutions of silver nitrate and other silver compounds are used as disinfectants and microbiocides (oligodynamic effect), added to bandages, wound-dressings, catheters, and other medical instruments.

Details

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.

Element Properties

atomic number : 47
atomic weight : 107.868
melting point : 960.8 °C (1,861.4 °F)
boiling point : 2,212 °C (4,014 °F)
specific gravity : 10.5 (20 °C [68 °F])
oxidation states : +1, +2, +3

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 color, malleability, ductility, and resistance to atmospheric oxidation, silver has long been used in the manufacture of coins, ornaments, and jewelry. Silver has the highest known electrical and thermal conductivity of all metals and is used in fabricating printed electrical circuits and as a vapor-deposited coating for electronic conductors; it is also alloyed with such elements as nickel or palladium for use in electrical contacts. Silver also finds use as a catalyst for its unique ability to convert ethylene to ethylene oxide, which is a precursor of many organic compounds. 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.

Unlike gold, silver is present in many naturally occurring minerals. For silver the more important deposits commercially are such compounds as the minerals tetrahedrite and argentite (silver sulfide, Ag2S), which is usually associated with other sulfides such as those of lead and copper, as well as several other sulfides, some of which contain antimony as well. Silver is found generally in lead ores, copper ores, and cobalt math 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.

Because the majority of the ores that contain silver also contain the important metals lead, copper, or zinc or a combination of the three, the silver-bearing fraction of these ores is frequently recovered as a by-product of copper and lead production. Pure silver is then recovered from the crude fraction by a combination of smelting and fire- or electrorefining.

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.

Alloys of silver with copper are harder, tougher, and more fusible than pure silver and are used for jewelry and coinage. The proportion of silver in these alloys is stated in terms of fineness, which means parts of silver per thousand of the alloy. Sterling silver contains 92.5 percent of silver and 7.5 percent of another metal, usually copper; i.e., it has a fineness of 925. Jewelry silver is an alloy containing 80 percent silver and 20 percent copper (800 fine). The yellow gold that is used in jewelry is composed of 53 percent gold, 25 percent silver, and 22 percent copper. (For treatment of silver’s use in ornamental and household objects, see metalwork.)

Natural silver consists of a mixture of two stable isotopes: silver-107 (51.839 percent) and silver-109 (48.161 percent). The metal does not react with moist air or dry oxygen but is oxidized superficially by moist ozone. It is quickly tarnished at room temperature by sulfur or hydrogen sulfide. In the molten state, silver can dissolve up to 22 times its volume of oxygen; on solidification, most of the oxygen is expelled, a phenomenon known as the spitting of silver. This can be controlled by the addition of a deoxidant such as charcoal to the molten silver. Silver dissolves readily in nitric acid and in hot concentrated sulfuric acid. The metal will also dissolve in oxidizing acids and in solutions containing cyanide ions in the presence of oxygen or peroxides. Dissolution in cyanide solutions is attributable to the formation of the very stable dicyanoargentate, [Ag(CN)2]−, ion.

Like copper, silver has a single s electron outside a completed d shell, but, in spite of the similarity in electronic structures and ionization energies, there are few close resemblances between silver and copper.

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.

Additional Information:

Appearance

Silver is a relatively soft, shiny metal. It tarnishes slowly in air as sulfur compounds react with the surface forming black silver sulfide.

Uses

Sterling silver contains 92.5% silver. The rest is copper or some other metal. It is used for jewellery and silver tableware, where appearance is important.

Silver is used to make mirrors, as it is the best reflector of visible light known, although it does tarnish with time. It is also used in dental alloys, solder and brazing alloys, electrical contacts and batteries. Silver paints are used for making printed circuits.

Silver bromide and iodide were important in the history of photography, because of their sensitivity to light. Even with the rise of digital photography, silver salts are still important in producing high-quality images and protecting against illegal copying. Light-sensitive glass (such as photochromic lenses) works on similar principles. It darkens in bright sunlight and becomes transparent in low sunlight.

Silver has antibacterial properties and silver nanoparticles are used in clothing to prevent bacteria from digesting sweat and forming unpleasant odours. Silver threads are woven into the fingertips of gloves so that they can be used with touchscreen phones.

Biological role

Silver has no known biological role. Chronic ingestion or inhalation of silver compounds can lead to a condition known as argyria, which results in a greyish pigmentation of the skin and mucous membranes. Silver has antibacterial properties and can kill lower organisms quite effectively.

Natural abundance

Silver occurs uncombined, and in ores such as argentite and chlorargyrite (horn silver). However, it is mostly extracted from lead-zinc, copper, gold and copper-nickel ores as a by-product of mining for these metals. The metal is recovered either from the ore, or during the electrolytic refining of copper. World production is about 20,000 tonnes per year.

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#1 2025-08-09 16:33:23

Silver

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