a set of reaction coordinates { ξ"j" }, avoiding the notion that the amounts of the components ( "N""i" ) can be changed independently. The expressions above are equal to zero at thermodynamic equilibrium, while in the general case for real systems, they are negative because all chemical reactions proceeding at a finite rate produce entropy. This can be made even more explicit by introducing the reaction "rates" d"ξ""j"/d"t". For each and every "physically independent" "process" (Prigogine & Defay, p. 38; Prigogine, p. 24)