(N/A) During the extraction of iron,the reduction of iron oxides takes place in the blast furnace. The furnace has different temperature zones,and the reactions are as follows:
$1.$ Lower temperature range (approx. $500-800 \ K$):
$3Fe_{2}O_{3} + CO \longrightarrow 2Fe_{3}O_{4} + CO_{2}$
$Fe_{3}O_{4} + 4CO \longrightarrow 3Fe + 4CO_{2}$
$Fe_{2}O_{3} + CO \longrightarrow 2Fe + 3CO_{2}$
$2.$ Higher temperature range (approx. $900-1500 \ K$):
$C + CO_{2} \longrightarrow 2CO$
$FeO + CO \longrightarrow Fe + CO_{2}$
$3.$ Formation of slag:
$CaCO_{3} \longrightarrow CaO + CO_{2}$
$CaO + SiO_{2} \longrightarrow CaSiO_{3} \text{ (Slag)}$
$4.$ At very high temperatures (approx. $2170 \ K$):
$C + O_{2} \longrightarrow CO_{2}$
$FeO + C \longrightarrow Fe + CO$