Chemistry - Metallurgy Question with Solution | TestHub

(i) Role of NaCN in the extraction of silver is to do the leaching of silver ore in the presence of air from which the silver is obtained later by replacement$\begin{array}{l}4\text{A}\text{g}(\text{s})+8\text{C}{\text{N}}^{-}(\text{a}\text{q})+2{\text{H}}_2\text{O}(\text{a}\text{q})+{\text{O}}_2(\text{g})\to {\left[\text{A}\text{g}{(\text{C}\text{N})}_2\right]}^{-}(\text{a}\text{q})+4\text{O}{\text{H}}^{-}(\text{a}\text{q})\\ 2{\left[\text{A}\text{g}{(\text{C}\text{N})}_2\right]}^{-}(\text{a}\text{q})+\text{Z}\text{n}(\text{s})\to 2\text{A}\text{g}(\text{s})+{\left[\text{Z}\text{n}{(\text{C}\text{N})}_4\right]}^{2-}(\text{a}\text{q})\end{array}$

(ii)$\text{Ti}+{\text{I}}_2\underset{}{\stackrel{\text{Δ}}{\to }}{\text{TiI}}_4\stackrel{\text{Δ}}{\to }\text{Ti}+{\text{I}}_2$(Van-Arkel method)
(iii) In the metallurgy of aluminium, cryolite lowers the melting point of the mixture and improves the electrical conductivity of the cell.