Question

Among C and CO which one is a better reducing agent Fe2O3 , above 1000K?

Answer 1

above 1000k C is better reducing agent bcoz above 1000k, gibb's energy for the formation of fe2o3 is more than the formation of co2 from C.

Answer 2

Answer: C is a better reducing agent for $Fe_2O_3$ than CO above 1000K.

Explanation:

Iron(III) oxide gets converted to iron by the process of reduction. The reducing agent used for reducing iron(III) oxide to iron is carbon monoxide and coke.

The equation for the reduction of iron oxide by coke, the reaction follows:

$FeO(s)+C(s)\rightarrow Fe(s/l)+CO(g)$  ....(1)

The two half reactions for thew above reaction is given by the equations:

Reduction:  $FeO(s)\rightarrow Fe(s)+\frac{1}{2}O_2(g)$   $\Delta G^o_{(FeO,Fe)}$

Oxidation: $C(s)+\frac{1}{2}O_2(g)\rightarrow CO(g)$    $\Delta G^o_{(C,CO)}$

The net free energy change of the above reactions is:   $\Delta G^o_{(FeO,Fe)}+\Delta G^o_{(C,CO)}=\Delta _rG^o$

Below 1000 K, $\Delta G^o$ formation of $Fe_2O_3$ is more than the formation of $CO_2$ from CO. So, CO is the reducing agent for $Fe_2O_3$ below 1000 K.

As, $\Delta G^o_{(FeO,Fe)}>\Delta G^o_{(C,CO)}$ above 1000 K. So, $\Delta _rG^o$ becomes negative and the reaction 1 becomes favourable.

Hence, C is a better reducing agent than CO above 1000 K.