Diseases, Conditions, Syndromes

A blood test will diagnose fibromyalgia more reliably

A research team from the University of Rovira i Virgili, University of Ohio and the University of Texas has developed an innovative method that allows fibromyalgia to be reliably diagnosed from a blood sample. Identifying ...

Other

Kariko calls Nobel win 'unbelievable'

Katalin Kariko, who won the Nobel Medicine Prize for work on messenger RNA (mRNA) technology, paving the way for COVID-19 vaccines, told Swedish media on Monday winning felt "unbelievable".

Inflammatory disorders

Wearable sweat sensor detects molecular hallmark of inflammation

The vast majority of diseases and disorders afflicting humans, ranging from arthritis to Zika fever, involve some level of inflammation. While inflammation is most familiar to us as pain, redness, and swelling, a slew of ...

Medical research

Researchers create new cancer fighting compound

A University of Kentucky Markey Cancer Center researcher's team developed new chemical compounds that show promise as a potential anticancer therapy to treat aggressive tumors.

Oncology & Cancer

Engineers report advance in rapid cancer detection and monitoring

When it comes to cancer detection, size matters. Traditional diagnostic imaging cannot detect tumors smaller than a certain size, causing missed opportunities for early detection and treatment. Circulating tumor exosomes ...

page 1 from 8

Gold

Gold (pronounced /ˈɡoʊld/) is a chemical element with the symbol Au (Latin: aurum) and an atomic number of 79. It has been a highly sought-after precious metal in jewelry, in sculpture, and for ornamentation since the beginning of recorded history. The metal occurs as nuggets or grains in rocks, in veins and in alluvial deposits. Gold is dense, soft, shiny and the most malleable and ductile pure metal known. Pure gold has a bright yellow color and luster traditionally considered attractive, which it maintains without oxidizing in air or water. It is one of the coinage metals and formed the basis for the gold standard used before the collapse of the Bretton Woods system in 1971.

At the end of 2006, it was estimated that all the gold ever mined totaled 158,000 tonnes. This can be represented by a cube with an edge length of just 20.2 meters. Modern industrial uses include dentistry and electronics, where gold has traditionally found use because of its good resistance to oxidative corrosion and excellent quality as a conductor of electricity. Chemically, gold is a transition metal and can form trivalent and univalent cations upon solvation. At STP it is attacked by aqua regia (a mixture of acids), forming chloroauric acid and by alkaline solutions of cyanide but not by single acids such as hydrochloric, nitric or sulfuric acids. Gold dissolves in mercury, forming amalgam alloys, but does not react with it. Since gold is insoluble in nitric acid which will dissolve silver and base metals, this is exploited as the basis of the gold refining technique known as "inquartation and parting". Nitric acid has long been used to confirm the presence of gold in items, and this is the origin of the colloquial term "acid test", referring to a gold standard test for genuine value.

This text uses material from Wikipedia, licensed under CC BY-SA