What is Chemical species?
{{For|the biology classification|species}} A '''chemical species''' is one of a group of [[atom]]s, [[molecule]]s, molecular [[wikt:fragment|fragment]]s, [[ion]]s, etc., made to go through to a [[chemical]] process or to a [[measurement]].<ref>{{Cite web |url=http://www.iupac.org/goldbook/C01038.pdf |title=IUPAC Gold Book definition of chemical species |access-date=2011-09-18 |archive-date=2007-09-27 |archive-url=https://web.archive.org/web/20070927085358/http://www.iupac.org/goldbook/C01038.pdf |url-status=dead }}</ref> Generally, a chemical species can be defined as an ensemble of chemically identical [[molecule|molecular]] entities that can [[wikt:explore|explore]] the same set of molecular [[energy level]]s on a defined time scale. Chemists also use chemical species to mean a set of chemically identical atomic or molecular structural units in a [[solid]] array. For example, when molecules of NaCl dissolve in water we don't really have any NaCl as such in the solution. We have Na<sup>+</sup> and Cl<sup>-</sup> ions because NaCl dissociates. We say the species present in solution are Na<sup>+</sup>(aq) and Cl<sup>-</sup>(aq). In this case, the species present in solution are the ions. In other cases, where the molecules don't dissolve in water, we would have molecular species in solution rather than ionic species.<ref>{{Cite web |url=http://dl.clackamas.cc.or.us/ch105-03/chemical1.htm |title=Chemical Species |access-date=2012-06-07 |archive-date=2012-12-30 |archive-url=https://web.archive.org/web/20121230065552/http://dl.clackamas.cc.or.us/ch105-03/chemical1.htm |url-status=dead }}</ref> In [[supramolecular chemistry]], chemical species are those supramolecular structures whose interactions and associations are brought about by forming or breaking intermolecular [[chemical bond|bond]]s. Studying these actions is the main topic of supramolecular chemistry. == References == <references/> [[Category:Chemistry]] {{chem-stub}}