Carbon monoxide is more effective reducing agent than carbon below `983 K` but above this temperature, the reverse is true. How would you explain this ?

Explanation

Consider production of iron from the oxide ore, haematite `Fe_(2)O_(3)`.The charge consists of iron ores (haematite, `Fe_(2)O_(3)`, and magnetite, `Fe_(3)O_(4))`. Coke and limestone is heated with a blasr of air. As the exothermic reaction proceeds a composition and temperature gradient is set up in the furnace. Below `1123 K, CO` reduces the ores to `FeO`. Reduction to `Fe` by `CO` can occur at about `823 K` and that direct reduction, in which the reducing agent is carbon can occur above `1123 K`. Hence carbom monoxide is an effective reducing agent than carbon below `983 K`.