where the standard equilibrium constant \(\displaystyle K^\circ = e^{\frac{1}{RT}\left(\gamma_C\mu_C^\circ+ \gamma_D\mu_D^\circ -\gamma_A\mu_A^\circ-\gamma_B\mu_B^\circ\right)}\) and the reaction quotient  \(\displaystyle Q_r = \frac{[C]^{\gamma_C}[D]^{\gamma_D}}{[A]^{\gamma_A}[B]^{\gamma_B}}\). Comparing the last line of equation (\ref{eqn:reaction-affinity-mass-action-ratio}) with the last line of equation (\ref{eqn:reaction-affinity-chemical-potential}), we see that the ratio of unknown forward and reverse rate constants is the standard equilibrium constant, which can be calculated from the standard chemical potentials using empirical methods such as the group contribution method and the component contribution method \cite{Jankowski2008}\cite{Mavrovouniotis1988} \cite{Noor2013}, or from nonempirical quantum chemistry methods such as density functional theory, post Hartree-Fock and molecular dynamics \cite{Jinich2014}.