The alumino-thermite process is used for the metallurgy of which metal?

In the extraction of copper from its sulphide ore,metal is finally obtained by the oxidation of cuprous sulphide with

Given below are two statements.
Statement $I$: According to the Ellingham diagram,any metal oxide with higher $\Delta G^{\circ}$ is more stable than the one with lower $\Delta G^{\circ}$.
Statement $II$: The metal involved in the formation of oxide placed lower in the Ellingham diagram can reduce the oxide of a metal placed higher in the diagram.
In the light of the above statements,choose the correct answer from the options given below.

When silica is present as an impurity in an ore,a/an ........ flux is required.

During the cyanide process,the silver complex ion formed is......

In the commercial electrochemical process for aluminium extraction,the electrolyte used is: