When alumina is heated with carbon in a nitrogen atmosphere,the products are

In smelting,the substance added to combine with impurities to form a molten product is called what?

Extraction of aluminium from bauxite ore,reduction is carried out by

With respect to an ore,the Ellingham diagram helps to predict the feasibility of its:

Choose the correct option with reference to the following statements:
$(1)$ Pig iron is produced at a temperature of $1270 \ K$.
$(2)$ Pig iron contains $4 \%$ carbon.
$(3)$ Pig iron cannot be cast into a variety of shapes.
$(4)$ Pig iron contains small amounts of impurities like $P, S, Si, Mn$.

In the extraction of which of the following metals is a complex salt formed?