What happens when iron oxide is reacted with carbon?

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t-nez | High School Teacher | (Level 3) Associate Educator

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When carbon reacts with iron(III)oxide it displaces the iron as follows:

`3 C + 4 Fe_2O_3 -> 4Fe + 3CO_2`

This is an example of a single replacement reaction. Carbon is more reactive than iron so it reduces iron from Fe3+ to Fe. The carbon is oxidized to carbon dioxide.

There are other oxides of iron that don't react with carbon. Fe2+ in FeO has a lower tendency to be reduced but it reacts with carbon monoxide in a blast furnace to produce steel. The high temperature causes the carbon to burn in oxygen and produce CO (carbon monoxide). The CO then reacts with FeO as follows:

`FeO + CO -> Fe + CO_2`

This reduces FeO to Fe and oxidizes CO to CO2.