The ground level of $\mathrm{Cl}$ is ${ }^2 \mathrm{P}_{3 / 2}$ and a ${ }^2 \mathrm{P}_{1 / 2}$ level lies $881 \mathrm{~cm}^{-1}$ above it. Calculate the electronic contribution to the molar Gibbs energy of $\mathrm{Cl}$ atoms at  $500 \mathrm{~K}$.
-6.42