In this reaction, carbon monoxide (CO) acts as a reducing agent and reduces iron oxide (FeO) to elemental iron (Fe). During this process, carbon monoxide itself gets oxidized to carbon dioxide (CO2).
The oxidation state of iron changes from +2 in FeO to 0 in Fe, indicating that iron undergoes oxidation in the reaction. On the other hand, the oxidation state of carbon changes from +2 in CO to +4 in CO2, indicating that carbon undergoes reduction.
