The Ellingham diagram is a graphical representation of

Assertion : Copper obtained after $Bessemerization$ is known as blister copper.
Reason : Blisters are produced on the surface of the metal due to escaping of dissolved $SO_2$.

Extraction of gold $(Au)$ involves the formation of complex ions $X$ and $Y$ as shown in the reaction: $\text{Gold ore}$ $\xrightarrow{CN^-, H_2O, O_2} HO^- + X$ $\xrightarrow{Zn} Y + Au$. $X$ and $Y$ respectively are:

Which metal is most difficult to be extracted from its oxide?

Which process is used for the extraction of copper from low-grade copper ores?

During the extraction of $Fe$,the slag obtained is: