To obtain silver from silver amalgam,it is heated in a vessel which is made of

Which of the following statements is correct regarding the slag obtained during the extraction of metals like copper and iron?

After partial roasting,the sulphide of copper is reduced by

In the electrolysis of alumina to obtain aluminium metal,cryolite is added mainly to

Which among the following processes occurs at $1500 \ K$ in a blast furnace for the extraction of iron?

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 $P, S, Si, Mn$.