Chromium is obtained by reducing concentrated chromite ore with

Which flux is used to remove $SiO_2$ impurity?

What is the reduction of $Cr_2O_3$ by heating it with aluminum called?

$I$. $FeCr_2O_4 + NaOH + \text{air} \rightarrow (A) + Fe_2O_3$
$II$. $(A) + (B) \rightarrow Na_2Cr_2O_7$
$III$. $Na_2Cr_2O_7 + X \xrightarrow{\Delta} Cr_2O_3$
$IV$. $Cr_2O_3 + Y \xrightarrow{\Delta} Cr$
High temperature $(> 1000 \ ^\circ C)$ electrolytic reduction is necessary for isolating:

Which of the following has the lowest percentage of carbon?

The chemical composition of the slag formed during the extraction of $Cu$ from copper pyrites is ......