Discussed are some of the issues which were considered when the International Union of Pure and Applied Chemistry revised its guide to notation in physical chemistry. Included are the choice between SI and non-SI units and choosing sensible names and symbols for quantities. (CW)

Discussed are the substructures (subgraphs) of imaginary transition structures that provide an effective approach to the characterization of organic reactions. A comparison of conventional methods and this method is presented. (CW)

Presented is a simple, unified approach to chemical nomenclature which employs the distinction between the terms chemical substance and chemical species. The classification of matter and chemical nomenclature are used as examples to illustrate this scheme. (CW)

Discussed is an extension of the conventional method for studying the organometallic chemistry of transition metals that may be useful to show how the various existing types of low-valence complexes can be constructed. This method allows students to design new types of complexes that may still be nonexistent. (CW)