Atom 13 : Nuclear Energy and Nuclear Disasters. The smallest particle of matter which can enter into chemical combination, i.e., iron (Fe), oxygen (O), hydrogen (H), carbon (C), chlorine (Cl). (COGWE, SSWID)
The Mudblogger (Oilfield, Energy and Related Photographs), Oil Field Glossary, TX, USA 2014. http://mudblogger.com/oilfield-glossary/, (Oil - Amer) {777}