Fundamentals of Chemical Engineering Thermodynamics

Chapter 14. Reactions

Up to this point we have concentrated exclusively on nonreacting systems, namely, systems in which the molecular identity of all species is preserved. In reactions, chemical identity is not preserved, as a reactant species is converted into a product species. Even so, the atomic identity of the constituent elements is preserved. In fact, a chemical reaction is simply a rearrangement of atoms into new molecules, and in this respect, is very similar to the passages of molecules from one phase into another. There are more analogies between chemical reactions and mixing of two liquids, for example. In both cases we observe the transition from an initial state to a final one that is accompanied by heat effects. A chemical reaction ...