The purest form of iron is prepared by oxidising impurities from cast iron in a reverberatory furnace. Which iron ore is used to line the furnace? Explain by giving the reaction.

(N/A) The lining of the reverberatory furnace is done using haematite $(Fe_{2}O_{3})$,which oxidises the impurities present in cast iron.
The reaction involved is:
$Fe_{2}O_{3} + 3C \rightarrow 2Fe + 3CO$
In this process,carbon is oxidised to $CO$. Other impurities like sulphur,silicon,and phosphorus are also oxidised to $SO_{2}$,$SiO_{2}$,and $P_{4}O_{10}$ respectively. $SO_{2}$ escapes as a gas,while $SiO_{2}$ and $P_{4}O_{10}$ are removed as slag by reacting with a flux.