$MO(s) + C(s) \to M(s) + CO(g)$ is spontaneous
$H_2O _{(g)} + C_{(s)} = CO_{(g)} + H_{2{(g)}}$; $\Delta H = 131\, KJ$, $CO_{(g)} + \frac{1}{2}\,O_{2{(g)}} = CO_2$$_{(g)}$ ; $\Delta H = -282\, KJ,H_2$ $_{(g)}$$+ \frac{1}{2}\,O_2$$_{(g)}$ $= H_2O$$_{(g)}$; $\Delta H = - 242\, KJ, $ $C_{(s)}$ $+ O_2$ $_{(g)}$ $= $ $ CO_2$ $_{(g)}$; $\Delta$ $H = - x\,\,KJ$
આપેલ : $\Delta H _{ f }{ }^\theta\left( Al _2 O _3\right)=-1700\,kJ\,mol ^{-1}$
$\Delta H _{ f }{ }^\theta\left( Fe _2 O _3\right)=-840\,kJ\,mol ^{-1}$
$Fe , Al$ અને $O$ નું મોલર દળ અનુક્રમે $56,27$ અને $16\,g\,mol ^{-1}$.
કિલોજૂલ અને $C + O_2$ $\rightarrow$ $CO_2$ :$\Delta H = x$ કિલોજૂલ, તો $x$ ..... કિલોજૂલ થાય.