Physical Chemistry Chapter 7 The phase rule At equilibrium, the chemical potential of a component j must be the same in every phase Aa=B=… for p phase That is, there are p-1 equations to be satisfied for each component 1. as there are c components, the tota number of equations is c(p-1) e each equation reduces the freedom to vary one of the plc-1)+2 intensive variables. It follows that the total variance Is f=p(c-1)+2-c(p-1)=c-p+2 1010 The Phase Rule At equilibrium, the chemical potential of a component j must be the same in every phase: That is, there are p-1 equations to be satisfied for each component j. as there are c components, the total number of equations is c(p-1). j, = j, =… for p phase Each equation reduces the freedom to vary one of the p(c-1)+2 intensive variables. It follows that the total variance is f = p(c-1) + 2 - c(p-1) = c – p + 2 Physical Chemistry Chapter 7