During the production of iron and steel.
A. The oxide ore is primarily reduced to iron by solid coke according to the reaction
`2Fe_(2)O_(3) + 3C rarr 4 Fe + 3CO_(2)`
B. The oxide ore is reduced by the carbon monoxide according to the reaction
`Fe_(2)O_(2) + 3CO rarr 2Fe + 3CO_(2)`
C. Major silica impurities are removed as calcium silicate slag by addition of a fluxing agent limestone
D. The silicate slag is used in manufacturing cement
