In the smelting of roasted copper pyrites ore,melting occurs so that the first reaction is:

Which of the following is the mixture used in the thermite process?

Which substance is used to provide a basic lining in a furnace?

Given below are two statements.
Statement $I:$ The choice of reducing agents for metals extraction can be made by using Ellingham diagram,a plot of $\Delta G$ vs temperature.
Statement $II:$ The value of $\Delta S$ increases from left to right in Ellingham diagram.
In the light of the above statements,choose the most appropriate answer from the options given below:

Carbon cannot be used to produce magnesium by chemical reduction of $MgO$ because

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 $3$.