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the hydrated proton, H3O+, a form in which hydrogen ion exists in aqueous solutions; also, H3O+·H2O, H3O+·2H2O, etc.
Synonym(s): oxonium ion
hydronium ion(hi-dro'ne-um) [G. Hydronium, abbr. of Hydroxonium ] See: ion
H3O+, a hydrated hydrogen ion. It is formed when an acid dissolves in water.
See also: ion