" Aquaregia is "

Aquaregia has the following composition-

(i)A black coloured compound (B) is formed on passing H_(2)S through the solution of a compound (A) in NH_(4)OH (ii) (B) on treatment with HCl and potassium chlorate or aquaregia gives (A) (iii) (A) on treatment with KCN gives a buff/reddish-brown coloured precipitate which dissolves in excess of this reagent forming a compound ( C) . (iv)The compound ( C) is changed into a compound (D) when its aqueous solution is boiled in air. (v)The solution of (A) was treated with excess of NaHCO_(3) & then with bromine water. On cooling & shaking for some time, a green colour of compound (E) is formed.No change is observed on heating. Identify (A) to (E) and give chemical equations.

Gold dissolves in cyanide solution the presence of air to form [Au(CN)_(3)] which is stable in a cons solution. Au_((s))+CN_((s))^(-)+O_(2)+H_(2)O_(2) hArr [Au(CN)_(2)]_((aq))^(-)+OH_((aq))^(-) Aquaregia a 3 : 1 mixture of conc. HC and HNO_(3) was developed by the alchemists as a means to dissolve gold. The process is actually a Redox reaction. Au_((s))+NO_(3(aq))+Cl^(-) hArr AuCl_(4(aq))^(-)+NO_(2(g)) Gold is too noble to react with HNO_(3) However gold does react with a waregia becuase the complex AuCl_(4)^(-) forms Au_((aq))^(+3)+3e^(-) to Au_((s)) E^(theta)=15V to I AuCl_(4(aq))^(-)+3e^(-) to Au_((s))+4Cl_((q))^(-)E^(0)=1V to 2 Calculate the formation constant approximately, of Auct at 25^(@)C

Gold dissolves in cyanide solution the presence of air to form [Au(CN)_(3)] which is stable in a cons solution. Au_((s))+CN_((s))^(-)+O_(2)+H_(2)O_(2) hArr [Au(CN)_(2)]_((aq))^(-)+OH_((aq))^(-) Aquaregia a 3 : 1 mixture of conc. HC and HNO_(3) was developed by the alchemists as a means to dissolve gold. The process is actually a Redox reaction. Au_((s))+NO_(3(aq))+Cl^(-) hArr AuCl_(4(aq))^(-)+NO_(2(g)) Gold is too noble to react with HNO_(3) However gold does react with a waregia becuase the complex AuCl_(4)^(-) forms Au_((aq))^(+3)+3e^(-) to Au_((s)) E^(theta)=15V to I AuCl_(4(aq))^(-)+3e^(-) to Au_((s))+4Cl_((q))^(-)E^(0)=1V to 2 How many grams, approximately of NACN are needed to extract 20g of gold from are?

Gold dissolves in cyanide solution the presence of air to form [Au(CN)_(3)] which is stable in a cons solution. Au_((s))+CN_((s))^(-)+O_(2)+H_(2)O_(2) hArr [Au(CN)_(2)]_((aq))^(-)+OH_((aq))^(-) Aquaregia a 3 : 1 mixture of conc. HC and HNO_(3) was developed by the alchemists as a means to dissolve gold. The process is actually a Redox reaction. Au_((s))+NO_(3(aq))+Cl^(-) hArr AuCl_(4(aq))^(-)+NO_(2(g)) Gold is too noble to react with HNO_(3) However gold does react with a waregia becuase the complex AuCl_(4)^(-) forms Au_((aq))^(+3)+3e^(-) to Au_((s)) E^(theta)=15V to I AuCl_(4(aq))^(-)+3e^(-) to Au_((s))+4Cl_((q))^(-)E^(0)=1V to 2 The function of HC is to provide C what is the purpose of the Cr in the above reaction select your choice from the following.

What is Aquaregia?