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Aqua regia (/ ˈ r eɪ ɡ i ə, ˈ r iː dʒ i ə /; from Latin, "regal water" or "royal water") is a mixture of nitric acid and hydrochloric acid, optimally in a molar ratio of 1:3. [b] Aqua regia is a fuming liquid. Freshly prepared aqua regia is colorless, but it turns yellow, orange or red within seconds from the formation of nitrosyl ...
Aqua regia (Latin: "royal water") – a mixture of aqua fortis and spirit of salt. Aqua tofani – arsenic trioxide, As 2 O 3 (extremely poisonous) Aqua vitae /aqua vita/spirit of wine, ardent spirits – ethanol, formed by distilling wine [2] Butter (or oil) of antimony – antimony trichloride.
To get the gold to a very high level of purity (999 fine gold) it is sometimes processed further with aqua regia to effectively remove all the impurities. Aqua regia was also used for parting. It was made by adding sal ammoniac to nitric acid which produced a mixture of hydrochloric acid and nitric acid.
It does react with selenic acid, and is dissolved by aqua regia, a 1:3 mixture of nitric acid and hydrochloric acid. Nitric acid oxidizes the metal to +3 ions, but only in minute amounts, typically undetectable in the pure acid because of the chemical equilibrium of the reaction.
aqua regia A liquid mixture of nitric acid (HNO 3) and hydrochloric acid (HCl), optimally in a molar ratio of 1:3, so named by historical alchemists because it is capable of dissolving the noble metals gold and platinum. aquation The process by which water molecules solvate or form coordination complexes with ions. [3] aqueous solution
If aqua regia is used, the chloride complexes are produced. Depending on the details of the process, which are often trade secrets, the individual PGMs are obtained as the following compounds: the poorly soluble (NH 4 ) 2 IrCl 6 and (NH 4 ) 2 PtCl 6 , PdCl 2 (NH 3 ) 2 , the volatile OsO 4 and RuO 4 , and [RhCl(NH 3 ) 5 ]Cl 2 .
A 3:1 mixture of concentrated hydrochloric acid and nitric acid, called aqua regia, is still stronger and successfully dissolves gold and platinum, because free chlorine and nitrosyl chloride are formed and chloride anions can form strong complexes.
aqua (aq.) water: aqua fortis: strong water: Refers to nitric acid, thus called because of its ability to dissolve all materials except gold and platinum aqua pura: pure water: Or, "clear water" or "clean water" aqua regia: royal water: Refers to a mixture of hydrochloric acid and nitric acid, thus called because of its ability to dissolve gold ...