Question

Calculate ΔG° for the reduction of Fe2O3 by CO at 25°C: Fe2O3(s) + 3CO(g) → 2Fe(s) + 3CO2(g) (ΔG°f data: CO2(g), –394.4 kJ/mol; Fe2O3(s), –741.0 kJ/mol; CO(g), –137.3kJ/mol) (Consider: Is the value that you calculate for ΔG° here the same value that you calculated for ΔG° using ΔH°f and S° data in the other question?)

+60.6 kJ

-60.6 kJ

-30.3 kJ

+30.3 kJ

-15.1 kJ

Answer 1

we have:

Gof(Fe2O3(s)) = -741.0 KJ/mol

Gof(CO(g)) = -137.3 KJ/mol

Gof(Fe(s)) = 0.0 KJ/mol

Gof(CO2(g)) = -394.4 KJ/mol

we have the Balanced chemical equation as:

Fe2O3(s) + 3 CO(g) ---> 2 Fe(s) + 3 CO2(g)

deltaGo rxn = 2*Gof(Fe(s)) + 3*Gof(CO2(g)) - 1*Gof( Fe2O3(s)) - 3*Gof(CO(g))

deltaGo rxn = 2*(0.0) + 3*(-394.4) - 1*(-741.0) - 3*(-137.3)

deltaGo rxn = -30.3 KJ/mol

Answer: -30.3 KJ/mol