ABSTRACT
For a chemical reaction to proceed, it is necessary that the reactant molecules come into intimate contact, a circumstance typically occurring with at least one of them in the fluid state. The equilibrium in a reactor involves, typically, several independent chemical reactions. A set of stoichiometric equilibria are said to be independent from each other if no reaction may be written as a linear combination of the others. The equilibrium constant is "constant" in that it does not change as the equilibrium composition changes, and this is the importance of having recognized its existence. However, its value depends, besides on temperature, on the stoichiometry used to write the reaction and on the choice of the standard state. The reaction equilibrium is displaced toward the reagents or the products as externally controlled parameters—temperature, pressure, amount of reacting species—are varied.
