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

Carbon can reduce ferric oxide to iron at a temperature above $983 \ K$ because

Which of the following is the correct chemical formula for slag?

Heating an ore with carbon in the absence of air is known as ....

Smelting is termed to the process in which

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.