In the process of extraction of gold,roasted | vedclass

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(A) The extraction of gold involves the leaching of gold ore with a dilute solution of $NaCN$ or $KCN$ in the presence of air $(O_2)$,which acts as an

Vedclass · Accepted Answer

$X = [Au(CN)_2]^-, Y = [Zn(CN)_4]^{2-}$

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(A) The extraction of gold involves the leaching of gold ore with a dilute solution of $NaCN$ or $KCN$ in the presence of air $(O_2)$,which acts as an oxidizing agent.The reaction is: $4Au(s) + 8CN^{-}(aq) + 2H_2O(aq) + O_2(g) 	o 4[Au(CN)_2]^{-}(aq) + 4OH^{-}(aq)$.Thus,$[X] = [Au(CN)_2]^{-}$.Gold is then recovered from the complex by displacement using zinc $(Zn)$:$2[Au(CN)_2]^{-}(aq) + Zn(s) 	o [Zn(CN)_4]^{2-}(aq) + 2Au(s)$.Thus,$[Y] = [Zn(CN)_4]^{2-}$.

In the process of extraction of gold,roasted gold ore reacts as follows. Identify the complexes $[X]$ and $[Y]$:
$\text{Roasted gold ore} + CN^{-} + H_2O \xrightarrow{O_2} [X] + OH^{-}$
$[X] + Zn \to [Y] + Au$

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In the process of extraction of gold,roasted gold ore reacts as follows. Identify the complexes $[X]$ and $[Y]$:$\text{Roasted gold ore} + CN^{-} + H_2O \xrightarrow{O_2} [X] + OH^{-}$$[X] + Zn \to [Y] + Au$