In the process of leaching of gold by cyanide | vedclass

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

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

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

In the process of leaching of gold by cyanide,what are the complexes $X$ and $Y$ respectively?
$4Au(s) + 8CN^-(aq) + 2H_2O(aq) + O_2(g) \to 4[Au(CN)_2]^-(aq) + 4OH^-(aq)$
$2[Au(CN)_2]^-(aq) + Zn(s) \to [Zn(CN)_4]^{2-}(aq) + 2Au(s)$
$X$ and $Y$ are:

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In the process of leaching of gold by cyanide,what are the complexes $X$ and $Y$ respectively?$4Au(s) + 8CN^-(aq) + 2H_2O(aq) + O_2(g) \to 4[Au(CN)_2]^-(aq) + 4OH^-(aq)$$2[Au(CN)_2]^-(aq) + Zn(s) \to [Zn(CN)_4]^{2-}(aq) + 2Au(s)$$X$ and $Y$ are: