Which among the following processes occurs at $1500 \ K$ in a blast furnace for the extraction of iron?

Which of the following is not a basic flux?

$I$. $FeCr_2O_4 + NaOH + \text{air} \rightarrow Na_2CrO_4 + Fe_2O_3$
$II$. $Na_2CrO_4 + H_2SO_4 \rightarrow Na_2Cr_2O_7$
$Na_2CrO_4$ and $Fe_2O_3$ are separated by:

$A$ metal has a high concentration in the Earth's crust and its oxides cannot be reduced by carbon. The most suitable method for the extraction of such metal is:

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

Which of the following statements is not correct?
$1$. Reduction of alumina to give aluminium by magnesium is thermodynamically feasible.
$2$. The point of intersection of $Al_2O_3$ and $MgO$ curves in Ellingham diagram is below $1665 \ K$.
$3$. Use of magnesium as reducing agent in metallurgy of aluminium is economical.
$4$. Ellingham diagram represents the graphical plot of Gibbs energy vs temperature for the formation of the oxides of common metals and reducing agents.