A green ore (A) of a metal present as a double /mixed compound is treated with HCl and then H_(2)S is passed in the solution. A back precipitate (B) is obtained, that is insoluble in yellow ammonium sulphide. The precipitate is dissolved in HNO_(3) and then excess of NH_(4)OH is added. The solution becomes coloured but this colour is discharged upon addition of KCN in excess due to the formation of compound (C). The solution of (A) in H_(2)O liberates a colourless and odourless gas on reaction with dilute H_(2)SO_(4) and solution of (A) gives white precipitate on addition of BaCl_(2) solution. The green ore (A) is ?

A green ore (A) of a metal present as a double /mixed compound is trea

1.	A green ore (A) of a metal present as a double /mixed compound is treated with HCl and then H_(2)S is passed in the solution. A back precipitate (B) is obtained, that is insoluble in yellow ammonium sulphide. The precipitate is dissolved in HNO_(3) and then excess of NH_(4)OH is added. The solution becomes coloured but this colour is discharged upon addition of KCN in excess due to the formation of compound (C). The solution of (A) in H_(2)O liberates a colourless and odourless gas on reaction with dilute H_(2)SO_(4) and solution of (A) gives white precipitate on addition of BaCl_(2) solution. The green ore (A) is ?
Answer» `CuSO_(4). Cu(OH)_(2)` `PbCO_(3).PB(OH)_(2)` `PbSO_(4).Pb(OH)^(2)` ` CuCO_(3).Cu(OH)_(2)` Answer :D