Question

The equilibrium constant $K_p$ for the homogeneous gaseous reaction is ${10}^{-3}$. The standard Gibbs free energy change $\Delta G^o$ for the reaction at ${27}^{o}C$ (sing $R=2cal{K}^{-1}{mol}^{-1}$) is_____________.

• A. Zero
• B. $-1.8kcal$
• C. $-4.154kcal$
• D. $+4.154kcal$

Answer 1

The correct option is D $+4.154kcal$

The equilibrium constant $K_p$ for the homogeneous gaseous reaction is ${10}^{-3}$. The standard Gibbs free energy change $\Delta G^o$ for the reaction at ${27}^{o}C$ (sing $R=2cal{K}^{-1}{mol}^{-1}$) is $+4.154kcal$.
$\Delta G^o=-RTln{K}_p$
$\Delta G^o=-2cal{K}^{-1}{mol}^{-1}\times 300K\times ln{10}^{-3}$
$\Delta G^o=+4.154kcal$