Chemical equilibrium in absence of external force fields implies no gradient of chemical potential, i=0, for each component and no affinity to go on, for each reaction The latter establishes i=1..C, Ar=0, r=1..R. a relation between molar fractions in the equilibrium composition and and for a given reaction xi, T p, 0=iMi, that for a reacting ideal gas mixture is (see ): (34) where the approximation lnK=A+B/T for the reaction constant has been applied, and the constants K gr (standard Gibbs function of reaction) and (standard enthalpy of reaction) are computed from the gr standard enthalpies and Gibbs functions of formation by: (35) For systems that are not at equilibrium yet, the ratio calculated from the mass-action law is called a reaction quotient The of a closed system have a tendency to reach a limiting value over time, Q. Q-values the equilibrium constant K.
Chemical equilibrium in absence of external force fields implies no gradient of chemical potential, i=0, for each component i=1..C, and no affinity to go on, Ar=0, for each reaction r=1..R. The latter establishes a relation between molar fractions in the equilibrium composition xi, and T and p, for a given reaction 0=iMi, that for a reacting ideal gas mixture is (see ): (34) where the approximation lnK=A+B/T for the reaction constant K has been applied, and the constants gr (standard Gibbs function of reaction) and gr (standard enthalpy of reaction) are computed from the standard enthalpies and Gibbs functions of formation by: (35) For systems that are not at equilibrium yet, the ratio calculated from the mass-action law is called a reaction quotient Q. The Q-values of a closed system have a tendency to reach a limiting value over time, the equilibrium constant K.