When bauxite powder is mixed with coke and reacted with nitrogen at $2075 \ K$, carbon monoxide and $X$ are formed. What is the gas formed when $X$ is reacted with water?

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:

Which of the following is $NOT$ an extraction process for silver?

Which of the following statements is incorrect regarding the electrolysis of $Al_2O_3$ by the Hall-Heroult process?

Which of the following metals is not obtained by electrolysis?

Predict conditions under which $Al$ might be expected to reduce $MgO$.