Royal water

Aqua regia, or "royal water," on the other hand, could dissolve gold. It turns out that the alchemists aqua regia was a mixture of concentrated hydrochloric and nitric acids. Either of these acids alone will not affect gold, but a mixture of the two dissolves the precious metal. 

Gold is very umeactive and does not dissolve in most acids. However, it does dissolve in aqua regia (Latin for royal water ), which is a mixture of concentrated hydrochloric and nitric acids. The unbalanced ionic equation for the reaction is as follows. 

Atomic chlorine attacks noble metals forming their respective chlorides (which are soluble in water). Alchemists named this mixture aqua regia (the royal water) because of its ability to dissolve gold and platinum. 

GeTe, mp. = 725 °C, can react with dense HCl solution, H2SO4 solution, and water when it is heated, while the mixture of royal water, H2O2, and HCl solution can erode it without heating. 

Aqua regia literally royal water , so called because it will dissolve gold a mixture of three parts concentrated hydrochloric acid to one part concentrated nitric acid Corundum structure o -alnminnm oxide stmctnre Electrochemical oxidation oxidation of a solnte by passing a direct electrical cnrrent through its solution (e.g. chlorine is produced industrially by the electrochemical oxidation of the chloride ion)... 

Aqua, n. Latin for water. Aqua regia means royal water. 

In the early 1800s, Smithson Tennant was studying platinum. He found that a black powder remained when platinum was dissolved in aqua regia. Aqua regia is a mixture of hydrochloric and nitric acids. The term aqua regia means royal water. It often dissolves materials that either acid by itself does not dissolve. 

A() REGIA, literally royal water, is one of the few reagents able to dissolve gold and platinum. It is a mixture of aqua fortis (nitric acid) and spirit of salt (hydrochloric acid). Best results are obtained using concentrated acids in the ratio 1 3 by volume. Aqua Regia looses its effectiveness so mix afresh for each use. 

Above a 16th-centuiy engraving of the green lion devouring the sun. In the comphcated alchemical symbolism, this can be translated as meaning that aqua regia (royal water)—a mixture of nitric and hydrochloric acids—dissolved gold, represented by the sun. 

Gold Is resistant to most acids but a fuming mixture of concentrated hydrochloric and nitric acids, known as Aqua Regia (meaning Royal Water ) does dissolve gold and this was the acid used in Bohr s laboratory. 

Libavius was the first to describe the preparation of hydrochloric acid, of tin tetrachloride, and of ammonium sulfate. He described also the preparation of aqua regia ( royal water ), a mixture of nitric acid and hydrochloric acid which receives its name from the fact that it can dissolve gold. He... 

Aqua regia translates to royal water in Latin, and it consists of a mixture of concentrated nitric and hydrochloric acids, typically in a 1 to 3 ratio, respectively. Since these are both strong acids, aqua regia can be quite dangerous and must be handled... 

Acids and bases have been known for millennia. For example, H2SO4 was known by the Sumerians, and most likely the acids HCl and HNO3 were also known since their mixture (called aqua regia— the royal water ) was used to dissolve gold. Alchemists discovered that the stomachs of humans and animals contain acid (HCl), and some of them like van Helmont, who we mentioned before, thought that acids are the force of life. Bases have been known for a long time, and they are even mentioned in the Bible (as neter ) as a means of laundering. 

Many of the early studies of the reactions of gold arose from the practice of alchemy, in which people attempted to turn cheap metals, such as lead, into gold. Alchemists discovered that gold can be dissolved in a 3 1 mixture of concentrated hydrochloric and nitric acids, known as aqua regia ("royal water"). The action of nitric acid on gold is similar to that on copper (Equation 4.32) in that the nitrate ion, rather than... 

Au does not react with either acid, but it will react with "royal water"—aqua regia (1 part HNO3 and 3 parts HCl). The HN03(aq) oxidizes the metal and CP from the HCl(aq) promotes the formation of fhe stable complex ion [AuCl4] . 

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