# How is Keq related to molality?

${K}_{e q} = \exp \left(\frac{- \Delta {G}^{0}}{R T}\right)$
where $\Delta {G}^{0}$ is the standard change in Gibbs Free Energy of the reaction under standard conditions. Standard conditions can be chosen as molarity (with a reference state of 1M) or molality (with a reference state of 1m), and the numerical value of Keq will be different depending on which reference state is chosen.