Euwebdesigns Link Directory
|House and home|
|Construction and Civil Engineering|
|Health and Food|
|Motor and Traffic|
|Education and IT|
|Tax rises needed 'to prevent NHS misery'|
|Yulia Skripal: 'We are so lucky to survive'|
|Trump lawyer 'paid by Ukraine' to arrange White House talks|
|Brexit deal cannot include return to hard border - Jeremy Corbyn|
|'Whistleblower' taped to chair and gagged|
|Trump barred from blocking Twitter users by judge|
|Grenfell Tower inquiry: Victim's son 'prays for death'|
|Met Police use more force against black people, figures suggest|
Gold is a chemical element with the symbol Au (from Latin: aurum "gold") and an atomic number of 79. Gold is a dense, soft, shiny, malleable and ductile metal. Pure gold has a bright yellow color and luster traditionally considered attractive, which it maintains without oxidizing in air or water. Chemically, gold is a transition metal and a group 11 element. It is one of the least reactive solid chemical elements. The metal therefore occurs often in free elemental (native) form, as nuggets or grains in rocks, in veins and in alluvial deposits. Less commonly, it occurs in minerals as gold compounds, usually with tellurium.
Gold resists attacks by individual acids, but it can be dissolved by the aqua regia (nitro-hydrochloric acid), so named because it dissolves gold. Gold also dissolves in alkaline solutions of cyanide, which have been used in mining. Gold dissolves in mercury, forming amalgam alloys. Gold is insoluble in nitric acid, which dissolves silver and base metals, a property that has long been used to confirm the presence of gold in items, giving rise to the term the acid test.