Question

Which of the following ore is concentrated using group 1 cyanide salt ?

<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> JEE Mains 2021

Answer 1

$\begin{array}{cc}\text{Ore}& \text{Formula}\\ \text{Sphalerite}& ZnS\\ \text{Siderite}& FeC{O}_3\\ \text{Malachite}& Cu(OH{)}_2.CuC{O}_3\\ \text{Calamine}& ZnC{O}_3\end{array}$

$ZnS+4NaCN\to \left[Zn\right(C{N}_4{]}^{2-}+4N{a}^{+}+S^{2-}$
the reagent $NaCN/KCN$ is used to suppress the floating characteristics of $ZnS$ by forming a soluble complex with $KCN.$