In isolation of which one of the following metals from their ores, the use of cyanide salt is not commonly involved?
Solution
In the extraction of Silver and Gold, NaCN is used
to leach the metal. <br/><br/>
$4\text{Au(s)} +8C\overline{N} (aq)+2H_{2}O+O_{2}(g)$ <br/><br/>
$\to 4\left[ Au(CN)_{2}\right]^{-} (aq)+4OH^{-}(aq)$<br/><br/>
$$
2\left[\mathrm{Au}(\mathrm{CN})_{2}\right]^{-}(\mathrm{aq})+\mathrm{Zn} \rightarrow 2 \mathrm{Au}(\mathrm{s})+\left[\left(\mathrm{Zn}(\mathrm{CN})_{4}\right)\right]^{2-}(\mathrm{aq})
$$<br/><br/>
In case of ore containing ZnS and PbS, the depressant used is NaCN.
About this question
Subject: Chemistry · Chapter: p-Block Elements · Topic: Group 13: Boron Family
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