How Do We Do That? To fi nd the quantitative relation between the equilibrium constants for the same reaction at two temperatures T1 and T2, we note that Eq. 8 allows us to write the relation between standard Gibbs free energies of reaction and the equilibrium con- stants K1 and K2 at the two temperatures: ¢Gr,1RT1 ln K1 ¢Gr,2RT2 ln K2 These two expressions rearrange to
ln K1 ¢Gr,1 RT1
ln K2 ¢Gr,2 RT2