$\Delta G_f^0$ and $\Delta H_f^0$ for Fe(g) are 370.7 $\mathrm{kJ\,mol^{-1}}$ and 416.3 $\mathrm{kJ\,mol^{-1}}$ at 298 K, respectively. Assuming $\Delta H_f^0$ is constant in the interval 250 K to 375 K, $\Delta G_f^0$ (rounded off to the nearest integer) for Fe(g) at 375 K is:
(a)338 $\mathrm{kJ\,mol^{-1}}$
(b)310 $\mathrm{kJ\,mol^{-1}}$
(c)325 $\mathrm{kJ\,mol^{-1}}$
(d)359 $\mathrm{kJ\,mol^{-1}}$
Answer
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