- hydrogen ion
ionized hydrogen of the form H+, found in aqueous solutions of all acids.[1895-1900]
* * *strictly, the nucleus of a hydrogen atom separated from its accompanying electron. The hydrogen nucleus is made up of a particle carrying a unit positive electric charge, called a proton (q.v.). The isolated hydrogen ion, represented by the symbol H+, is therefore customarily used to represent a proton. Because the bare nucleus can readily combine with other particles (electrons, atoms, and molecules), the isolated hydrogen ion can exist only in a nearly particle-free space (high vacuum) and in the gaseous state.In common usage, the term hydrogen ion is used to refer to the hydrogen ion present in water solutions, in which it exists as the combined molecule H+·H2O.The formula H+·H2O is also commonly written as H3O+ and denotes the hydronium or oxonium ion. The amount of hydrogen ion present in a water solution is used as a measure of the acidity of a substance; the higher the concentration of hydrogen ion the more acidic the solution and the lower the pH. See also pH.
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Hydrogen ion — is recommended by IUPAC as a general term for all ions of hydrogen and its isotopes. [ Compendium of Chemical Terminology , 2nd edition McNaught, A.D. and Wilkinson, A. Blackwell Science, 1997 [ISBN 0 86542 684 8] , also… … Wikipedia
Hydrogen ion — Hydrogen er et grundstof. Et hydrogen atom angives tit bare med et H. Hvis hydrogen atomet mangler en elektron, vil det gerne reagere med andre grundstoffer og molekyler. Når det sker kaldes hydrogen i stedet for en hydrogen ion. En hydrogen ion… … Danske encyklopædi
hydrogen ion — or hydrogen n. 1. the positively charged nucleus of hydrogen, H+, without its electron 2. HYDRONIUM ION … English World dictionary
hydrogen ion — n 1) the cation H+ of acids consisting of a hydrogen atom whose electron has been transferred to the anion of the acid 2) HYDRONIUM * * * the nucleus of the hydrogen atom or a hydrogen atom that has lost its electron, H+; it bears a positive… … Medical dictionary
hydrogen ion — noun a positively charged atom of hydrogen; that is to say, a normal hydrogen atomic nucleus • Hypernyms: ↑proton, ↑cation • Part Holonyms: ↑hydrogen atom * * * noun 1. : the cation H+ of acids consisting of a hydrogen atom wh … Useful english dictionary
hydrogen ion — noun Date: 1896 1. the cation H+ of acids consisting of a hydrogen atom whose electron has been transferred to the anion of the acid 2. hydronium … New Collegiate Dictionary
hydrogen ion — hy′drogen i′on n. chem. ionized hydrogen of the form H+, found in aqueous solutions of all acids • Etymology: 1895–1900 … From formal English to slang
hydrogen ion — noun a) ; H or H b) a proton combined with one or more water molecules; usually written HO and called the hydronium ion though is best considered as HO but is often written H for simplicity … Wiktionary
hydrogen ion — /ˈhaɪdrədʒən aɪən/ (say huydruhjuhn uyuhn) noun a proton, H+, existing as a hydronium ion, H3O+ in aqueous solution … Australian English dictionary
hydrogen ion concentration — hydrogen ion concentration. См. водородный показатель. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) … Молекулярная биология и генетика. Толковый словарь.