Equilibrium Conditions in Multicomponent Systems

This chapter applies equilibrium theory to a variety of chemical systems of more than one component. Two different approaches will be used as appropriate one based on the relation Ilf = 11 for transfer equilibrium, the other based on v//r/ = 0 or AT = Wiof for reaction equilibrium. 

For some of the derivations in this chapter, we will need an expression for the rate at which the ratio jit / T varies with temperature in a phase of fixed composition maintained at constant pressure. This expression leads, among other things, to an important relation between the temperature dependence of an equilibrium constant and the standard molar reaction enthalpy. 

In a phase containing species i, either pure or in a mixture, the partial derivative of in / T with respect to T at constant p and a fixed amount of each species is given by  

This equality comes from a purely mathematical operation no thermodynamics is involved. The partial derivative (dlii/dT)p .j is equal to —5/ (Eq. 9.2.48), so thatEq. 12.1.1 becomes 

Eor a pure substance in a closed system, Eq. 12.1.3 when multiplied by the amount n becomes 

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CHAPTER 12 EQUILIBRIUM CONDITIONS IN MULTICOMPONENT SYSTEMS 12.1 Effects OF Temperature... 

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