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 5. 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 Gold Podcast Transcript :. You're listening to Chemistry in its element brought to you by Chemistry World , the magazine of the Royal Society of Chemistry.
Hello, in this week's episode of Chemistry in its element, we're taking a flight on Concorde, dropping by Buckingham Palace and finding out what could form a film just atoms thick.
Going for gold for us this week, here's the legendary science broadcaster and populariser Johnny Ball. The element gold. Gold is element 79 and its symbol is Au. Though the name is Anglo Saxon, gold originated from the Latin Aurum, or shining dawn, and previously from the Greek. It's abundance in the earth's crust is 0. Gold along with silver and copper, form a column in the periodic table. They are found naturally and were the first three elements known to man. They were all used as primitive money well before the first gold coins which appeared in Egypt around BC.
Most gold is ancient or comes from Central American Aztecs and South American Incas brought to Europe by the Spanish and Portuguese in the 16th century, and which has since been recycled over and over again. In world output was no more than 12 tonnes per annum.
But around that time, new gold discoveries were being made. World production was then around tonnes per year. It is now around tones per annum.
Because it is found in it's natural state and does not naturally alloy with anything else and because it is the heaviest metal, by sifting rock in water, the gold always falls to the bottom and all less dense impurities are washed away. The largest nugget was the Welcome Stranger nugget found in Victoria, Australia in It weighed over 71 kg. This type of nugget occurs naturally, but is very, very rare. Pure gold is 24 karat.
Gold is the most malleable of all metals and soft enough to be cut with a knife. Stone age peoples hammered gold into plates for ornamental purposes. Really quite large amounts were gathered together. Though King Tutankhamun was a minor Pharaoh and died aged 18, his coffin alone contained kg of gold. Egyptians also made thin gold sheets, utensils, vast varieties of jewellery and even gold thread.
King Tut when he was buried had over gold ornaments on his body. Today 1 gram can be beaten into a square metre sheet just atoms thick. Concord's windscreen had a layer of gold to screen pilots from UV light and today it is often used in sky scraper windows to cut down both heat and UV from sunlight.
The gold colour in the Buckingham Palace fence is actually gold covered, as it lasts 30 years, whereas gold paint which contains no gold at all lasts in tip top condition, only about a year. Sea water contains around 3 parts in a billion of gold, but there's never been found an economic means of recovering it. The Germans tried very hard during the second World War but failed miserably.
It is estimated that all the world's gold gathered together would only make a cube around 18 metres per side - about cubic metres. And that's gold.
So now you know why pirates used to bite gold coins to see if they were real. It wasn't just for the camera because it looked good, it was because the metal was soft enough to be marked by teeth.
That was Johnny Ball telling the story of gold. Next time on Chemistry in its element Victoria Gill introduces the chemical that founded the science of photography and also helped to launch the careers of successions of Oscar winners. The effect was seen as magical, a devilish art. 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.
And you can hear Victoria Gill crossing your cognitive palm and lining your intellectual pocket with silver 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 Gold. 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. The elemental symbol of gold is Au, a throwback to its Latin name, Aurum. Gold's atomic number is It's atomic weight is The gold created by these reactions was a kind of cosmic dust that accumulated as the planets of our solar system formed thus creating the gold deposits found on earth. The words for gold in both Anglo-Saxon and Latin are references to its deep yellow color.
The Anglo-Saxon word, geolo, which later transformed into the modern word, gold, literally means yellow. The Latin word for gold, Aurum, is translated to mean shining dawn.
In modern language, gold has entered the vernacular with phrases such as golden brown, golden hair, gold standard and other similar entries. Read more common gold questions.
All rights reserved. Common gold questions. Gold is a good conductor of heat and electricity and does not tarnish when it is exposed to the air, so it can be used to make electrical connectors and printed circuit boards. Gold is also a good reflector of infrared radiation and can be used to help shield spacecraft and skyscrapers from the sun's heat. Gold coated mirrors can be used to make telescopes that are sensitive to infrared light. A radioactive isotope of gold, gold, is used for treating cancer.
Gold sodium thiosulfate AuNa 3 O 6 S 4 is used as a treatment for arthritis. Chlorauric acid HAuCl 4 is used to preserve photographs by replacing the silver atoms present in an image. Number of Stable Isotopes : 1 View all isotope data. Gold has not been evaluated for its ecotoxicity. However, the biodegradation of gold under aerobic conditions is expected to be very poor and there is no evidence to suggest it creates ecological problems when released into the environment.
Since gold is insoluble, it is believed to have minimal bioaccumulation and bioavailability characteristics. Click here for more historical data on the price of gold. Back to periodic chart. Toggle navigation. Home Periodic table Elements Gold. About Lenntech. General Delivery Conditions.
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