(chemistry) The study of the effects of isotopic substitution on chemical compounds, especially on the kinetics of their reactions.

The branch of soil science that deals with the chemical properties, constituents and reactions within soils.

(chemistry) The application of chemical techniques to the solution of problems in nuclear physics, including the discovery of naturally occurring and synthetic radioactive elements and the results of nuclear fission.

(chemistry, physics) the application of quantum mechanics to chemical problems

(physics, chemistry) The study of the chemical changes that result from the absorption of ionizing radiation.

(informal, chemistry) Any of the traditional methods and techniques of chemistry, especially those of analytical chemistry that use gravimetric analysis or volumetric analysis rather than spectroscopy.

(mathematics, chemistry) The use of computation to predict the structure, properties and reactions of molecules

(pathology) Branch of pathology concerned with the chemical analysis of bodily fluids etc.

(informal, chemistry) Any chemical process or technique that is relatively low-tech, and does not require specialist equipment or skills, or precise measurement or control.

(chemistry) An area of chemistry and chemical engineering focused on the designing of products and processes that minimize the use and generation of hazardous substances.