At 1500 K the standard Gibbs energies of formation of oxides per mole of O2 are: 4/3 Al + O2 -> 2/3 Al2O3, -820 kJ; 2Fe + O2 -> 2FeO, -380 kJ. Using these data, Delta G deg at 1500 K for 3FeO + 2Al -> Al2O3 + 3Fe is

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At $1500 K$ the standard Gibbs energies of formation of oxides per mole of $O X_{2}$ are: $\frac{4}{3} Al + O X_{2} \frac{2}{3} Al X_{2} O X_{3}$ , $- 820 kJ$ ; $2 Fe + O X_{2} 2 FeO$ , $- 380 kJ$ . Using these data, $Δ G^{\circ}$ at $1500 K$ for $3 FeO + 2 Al Al X_{2} O X_{3} + 3 Fe$ is

The reaction uses

1.5

mol of

O X_{2}

equivalents. Multiply the aluminium line by

1.5

to get

- 1230 kJ

, and reverse the iron line scaled by

1.5

to get

+ 570 kJ

. The sum is

- 1230 + 570 = - 660 kJ

, so aluminium reduces FeO spontaneously.