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, tonnes per year.
Help text not available for this section currently. Elements and Periodic Table History. Slag heaps near ancient mine workings in Turkey and Greece prove that silver mining started around BC. The metal was refined by cupellation, a process invented by the Chaldeans, who lived in what is now southern Iraq. It consisted of heating the molten metal in a shallow cup over which blew a strong draft of air. This oxidised the other metals, such as lead and copper, leaving only silver unaffected.
The rise of Athens was made possible partly through the exploitation of local silver mines at Laurium. These operated from BC and right through the Roman era. In Medieval times, German mines became the main source of silver in Europe. Silver was also mined by the ancient civilizations of Central and South America there being rich deposits in Peru, Bolivia and Mexico. Atomic data. Glossary Common oxidation states The oxidation state of an atom is a measure of the degree of oxidation of an atom.
Oxidation states and isotopes. Glossary Data for this section been provided by the British Geological Survey. Relative supply risk An integrated supply risk index from 1 very low risk to 10 very high risk. Recycling rate The percentage of a commodity which is recycled. Substitutability The availability of suitable substitutes for a given commodity.
Reserve distribution The percentage of the world reserves located in the country with the largest reserves. Political stability of top producer A percentile rank for the political stability of the top producing country, derived from World Bank governance indicators. Political stability of top reserve holder A percentile rank for the political stability of the country with the largest reserves, derived from World Bank governance indicators. Supply risk.
Relative supply risk 6. Young's modulus A measure of the stiffness of a substance. Shear modulus A measure of how difficult it is to deform a material. Bulk modulus A measure of how difficult it is to compress a substance.
Vapour pressure A measure of the propensity of a substance to evaporate. Pressure and temperature data — advanced. Listen to Silver Podcast Transcript :. You're listening to Chemistry in its element brought to you by Chemistry World , the magazine of the Royal Society of Chemistry. Welcome to Chemistry in its element. This week, we're demystifying the element behind the photograph and to cross your cognitive palm with silver, here's Victoria Gill.
Its lustre shine has been coveted since ancient times. It's not just rare or precious, as its more expensive cousin, gold, but there is evidence from as early as BC that humans extracted silver from naturally occurring silver sulphide deposits in rocks to make coins and jewellery.
These coins actually form the basis for the economies of some ancient Mediterranean civilizations. It's a soft and pliable metal with a relatively low melting point and that means it can be hammered and moulded into shape, so the same metal that was used to make money that was gradually outdated could also be transformed into vases, platters, cutlery and goblets; tableware that has created displays of household wealth through the centuries.
But a gleaming collection of silverware isn't easy to maintain. The metal reacts with sulphur in the air, rapidly forming a dull, dark silver sulphide tarnish that has to be polished off. So it's a high maintenance element; another reason why it has always been outshone by gold. But the same chemical properties that tarnished its image let it to make another mark in history, by allowing history itself to be recorded in the photograph.
In , a German physicist called Johann Heinrich Schulze found that a paste of chalk and silver nitrate salt was blackened by light.
He used stencils to produce black images with the paste. This reaction, the dawn of photography, was all thanks to the fact that silver salts are sensitive to light.
A photon of light hitting the negative nitrate anion frees an electron, which ultimately combines with the positive silver ions to make neutral silver metal, darkening the surface of the material. When in , Henry Talbot discovered an additional chemical twist, that is so called latent silver image, that had been briefly exposed onto a layer of silver iodide could be revealed using gallic acid, the effect was seen as magical, a devilish art.
But this mystical development of an invisible picture was a simple reduction reaction; the gallic acid helping to reduce photosensitized silver ions into silver metal. Hollywood could never have existed without the chemical reaction that gave celluloid film its ability to capture the stars and bring them to the aptly dubbed silver screen.
Digital photography may now have eclipsed the silver image, but the metal's ability to conduct has given it an important role in the digital age. Silver is used on circuit boards and in batteries, where the conduction speed is needed that copper for example, can't quite deliver.
Even its most outdated properties are making resurgence. With new antibiotics running thin, a few researchers are returning to silver as a coating to keep the bugs at bay. Silver metal is toxic to nasty bacteria, but not to us and there is even a tiny amount of it in our bodies, but that's yet to give up the secret of why it's there.
For me, rather superficially, it's always been gold's subtler, prettier counterpart. Victoria Gill uncovering the secrets of the element that gave us the silver screen.
Next time on Chemistry in its element, John Emsley introduces a chemical that's mostly fallen from favour, perhaps with good reason. This trouble-making element has attacked the ozone layer, and its mere presence has caused entire reservoirs to be drained. And you can hear John Emsley telling the story of the brown element, bromine, on next week's Chemistry in its element.
I'm Chris Smith, thank you for listening. See you next time. Chemistry in its element is brought to you by the Royal Society of Chemistry and produced by thenakedscientists. There's more information and other episodes of Chemistry in its element on our website at chemistryworld.
Click here to view videos about Silver. View videos about. Help Text. Learn Chemistry : Your single route to hundreds of free-to-access chemistry teaching resources. We hope that you enjoy your visit to this Site. We welcome your feedback. Data W. Haynes, ed. Version 1. Coursey, D. Silver ore is easy to reduce. Silver ore is found in native form. The other principal sources of silver are copper, copper-nickel, gold, lead and lead-zinc ores. Silver is used in medicine for its caustic, astringent, and antiseptic effects.
Site Index. Transition Metals. Atomic Number. Periodic Table. What is the element Silver as on the Periodic Table? Medical uses of Silver - Health and Treatments. Medical Disorders. Medical Symptoms. Silver dental alloys are used in soldering and as cones to obliterate the root canal. Conjunctivitis in newborn babies. Silver nitrate, absorbed as an antiseptic. Skin infections in patients resulting from extensive burns or industrial exposure.
Eye contact: may cause severe corneal injury if liquid comes in contact with the eyes. Skin contact: may cause skin irritation. Repeated and prolonged contact with skin may cause allergic dermatitis. Inhalation hazards: exposure to high concentrations of vapors may cause dizziness, breathing difficulty, headaches or respiratory irritation.
Extremely high concentrations may cause drowsiness, staggering, confusion, unconsciousness, coma or death. Liquid or vapor may be irritating to skin, eyes, throat, or lungs. Intentional misuse by deliberately concentrating and inhaling the contents of this product can be harmful or fatal. Ingestion hazards: moderately toxic. May cause stomach discomfort, nausea, vomiting, diarrhea, and narcosis. Aspiration of material into lungs if swallowed or if vomiting occurs can cause chemical pneumonitis which can be fatal.
Target organ: chronic overexposure to a component or components in this material has been found to cause the following effects in laboratory animals:. Chronic overexposure to a component or components in this product has been suggested as a cause of the following effects in humans:.
For information on: - Environmental levels - Effects of organisms in the laboratory and field - Aquatic environment: Toxicity of silver compounds to aquatic species - Terrestrial environment - Effects evaluation.
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