The slag obtained during the extraction of copper from copper pyrites is composed mainly of

Upon heating with $Cu_2S$,the reagent$(s)$ that give copper metal is/are:
$(A)$ $CuFeS_2$
$(B)$ $CuO$
$(C)$ $Cu_2O$
$(D)$ $CuSO_4$

Explain the extraction of elements by oxidation.

The modern method for the manufacture of steel is:

During the electrolytic reduction of alumina,two auxiliary electrolytes $X$ and $Y$ are added to increase the electrical conductance and lower the melting point of the mixture. $X$ and $Y$ are:

Aluminium is obtained by: