Chemistry. (def 7).
a process that involves changes in the structure and energy content of atoms, molecules, or ions but not their nuclei Compare nuclear reaction
A process in which atoms of the same or different elements rearrange themselves to form a new substance. While they do so, they either absorb heat or give it off.
noun 1. an allergic sensitivity to particular chemicals in air, food, clothing, water, etc.
- Chemical repair
chemical repair n. Conversion of a free radical to a stable molecule.
- Chemical symbol
noun an abbreviation or short representation of a chemical element; the symbols in the periodic table Examples Natural elements all have chemical symbols of one or two letters; some manmade elements have three-letter symbols.
noun, Medicine/Medical. 1. (def 2). [sim-puh-thek-tuh-mee] /ˌsɪm pəˈθɛk tə mi/ noun, plural sympathectomies. Medicine/Medical. 1. surgery that interrupts a nerve pathway of the or involuntary nervous system. 2. Also called chemical sympathectomy. a like interruption by chemical means. /ˌsɪmpəˈθɛktəmɪ/ noun (pl) -mies 1. the surgical excision or chemical destruction (chemical sympathectomy) of one or more […]