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प्रश्न
Write the chemical reactions involved in the extraction of gold by cyanide process. Also give the role of zinc in the extraction.
उत्तर
\[\ce{4Au(s) + 8CN^{-} (aq) + 2H2O (aq) + O2(g) -> 4[Au(CN)2]^{-} (aq) + 4OH^{-} (aq)}\]
\[\ce{2[Au(CN)2]^{-} (aq) + Zn(s) -> 2Au(s) + [Zn(CN)4]^{2-} (aq)}\]
Zinc places the role of a reducing agent. It reduces \[\ce{Au+}\] to pure \[\ce{Au}\].
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संबंधित प्रश्न
Write the names and chemical formulae of any one ore of zinc.
Silica is added to roasted copper ore during smelting process to remove _______.
(A) ferrous sulphide
(B) ferrous oxide
(C) cuprous sulphide
(D) cuprous oxide
Draw neat and labelled diagram of Bessermer converter used in the extraction of copper.
What is the role of cryolite in the extraction of aluminium?
Which form of the iron is the purest form of commercial iron?
Name the method used for refining of copper metal.
In the extraction of zinc from zinc blende:
(i) Give an equation to show how zinc oxide is converted to zinc.
(ii) How is impure zinc finally electro-refined?
The most abundant metal on earth is:
The main reactions occurring in blast furnace during extraction of iron from haematite are:
(i) \[\ce{Fe2O3 + 3CO -> 2Fe + 3CO2}\]
(ii) \[\ce{FeO + SiO2 -> FeSiO3}\]
(iii) \[\ce{Fe2O3 + 3C -> 2Fe + 3CO}\]
(iv) \[\ce{CaO + SiO2 -> CaSiO3}\]
The ore that contains both iron and copper is ______.
