Hydrogen ion 529019 203310092 2008-04-04T15:59:20Z Plumbago 125900 /* Anion (negatively charged) */ added "See also" '''Hydrogen ion''' is recommended by [[IUPAC]] as a general term for all [[ion]]s of [[hydrogen]] and its [[isotope]]s.<ref>''Compendium of Chemical Terminology'', 2nd edition McNaught, A.D. and Wilkinson, A. Blackwell Science, 1997 [ISBN 0-86542-684-8], also [http://www.iupac.org/publications/compendium/index.html online]</ref> Depending on the [[charge]] of the ion, two different classes can be distinguished: ==Cation (positively charged)== When hydrogen loses its [[electron]], the following [[cation]]s can be formed: * [[Hydron (chemistry)|Hydron]]: general name referring to the positive ion of any hydrogen isotope (H<sup>+</sup>) * [[Proton]]: <sup>1</sup>H<sup>+</sup> * [[Deuteron]]: <sup>2</sup>H<sup>+</sup>, D<sup>+</sup> * Triton: <sup>3</sup>H<sup>+</sup>, T<sup>+</sup> In addition, the ions produced by the reaction of these cations with [[water]] as well as their [[hydrates]] are called hydrogen ions: * [[Hydronium]] ion: H<sub>3</sub>O<sup>+</sup> * '''Zundel cation''': H<sub>5</sub>O<sub>2</sub><sup>+</sup> * '''Eigen cation''': H<sub>9</sub>O<sub>4</sub><sup>+</sup> The latter two play an important role in proton hopping according to the [[Grotthuss mechanism]]. In connection with acids, hydrogen ions typically refer to [[Hydron (chemistry)|hydrons]]. ==Anion (negatively charged)== Hydrogen [[anion]]s are formed when additional electrons are acquired: * [[Hydride]]: general name referring to the negative ion of any hydrogen isotope * Deuteride: <sup>2</sup>H<sup>-</sup>, D<sup>-</sup> * Tritide: <sup>3</sup>H<sup>-</sup>, T<sup>-</sup> In [[organic chemistry]], a hydrogen atom in a molecule is often referred to simply as a proton. The [[hydrogen anion]] has played an important role in quantum physics. ==See also== * [[Acid]] * [[PH|pH]] ==References== {{reflist}} [[Category:Hydrogen physics]] [[de:Wasserstoffion]] [[sv:Vätejon]]