During the smelting of roasted copper ore,silica is added to remove:

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:

The compound$(s)$ that is(are) removed as slag during the extraction of copper is:
$1. CaO$
$2. FeO$
$3. Al_{2}O_{3}$
$4. ZnO$
$5. NiO$
Choose the correct answer from the options given below.

The purpose of smelting in metallurgy is ...........

Which of the following statements is incorrect?

An Ellingham diagram provides information about :