In a blast furnace,the highest temperature is in the:

The final step for the extraction of copper from copper pyrite in the Bessemer converter involves the reaction:

In the electrolytic reduction of alumina,why is cryolite $(Na_3AlF_6)$ primarily added?

Predict conditions under which $Al$ might be expected to reduce $MgO$.

Copper is the most noble of the first row transition metals and occurs in small deposits in several countries. Ores of copper include chalcanthite $(CuSO_4 \cdot 5H_2O)$,atacamite $(Cu_2Cl(OH)_3)$,cuprite $(Cu_2O)$,copper glance $(Cu_2S)$ and malachite $(Cu_2(OH)_2CO_3)$. However,$80\%$ of the world copper production comes from the ore of chalcopyrite $(CuFeS_2)$. The extraction of copper from chalcopyrite involves partial roasting,removal of iron and self-reduction. $1.$ Partial roasting of chalcopyrite produces: $(A)$ $Cu_2S$ and $FeO$ $(B)$ $Cu_2O$ and $FeO$ $(C)$ $CuS$ and $Fe_2O_3$ $(D)$ $Cu_2O$ and $Fe_2O_3$. $2.$ Iron is removed from chalcopyrite as: $(A)$ $FeO$ $(B)$ $FeS$ $(C)$ $Fe_2O_3$ $(D)$ $FeSiO_3$. $3.$ In self-reduction,the reducing species is: $(A)$ $S$ $(B)$ $O^{2-}$ $(C)$ $S^{2-}$ $(D)$ $SO_2$. Give the answer for questions $1, 2$ and $3$.

The temperature at which carbon reduces $FeO$ into iron and produces $CO$ is: