In the extraction of $Zn$,which gas is burnt in the jackets surrounding the retorts?

Which substance is used as a flux to remove acidic impurities in metallurgy?

During the electrolytic reduction of alumina,two auxiliary electrolytes $X$ and $Y$ are added to increase the electrical conductance and lower the melting point of the mixture. $X$ and $Y$ are:

For which of the following metals is the self-reduction process $NOT$ used?

In the extraction of copper,metal is formed in the Bessemer converter due to the reaction:

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.