Write down the reactions taking place in different zones in the blast furnace during the extraction of iron.

Explanation

Pig iron - Iron obtained from furnace ocntains about `4%` carbon and impurities [S,P,SiMn] is smaller amount.
Cast iron -It is made by melting pig iron with scrap iron and coke using hot air blast. It contain `3%` carbon and is extremely hard and brittle.