Question

The equilibrium constant $K_p$ for a homogeneous gaseous reaction is $10^{-8}$. The standard Gibbs free energy change $\Delta G^{\ominus}$ for the reaction (using $R=2 \,cal ^{-1} mol ^{-1}$ ) is

• A. $10.98 \,kcal$
• B. $-1.8\, kcal$
• C. $-4.1454 \,kcal$
• D. $+4.1454 \,kcal$

Answer 1

Answer: (A)

$\Delta G^{\ominus}=-2.303 R T \log K$
$=-2.303 \times 2 \times 298 \log 10^{-8}$
$=-2.303 \times 2 \times 298 \times-8\, cal$
$=10980 \,cal =10.98\, kcal$