abstract:In chemistry, an onium compound, or onium ion, is a cation formally obtained by the protonation of mononuclear parent hydride of a pnictogen (group 15 of the periodic table), chalcogen (group 16), or halogen (group 17). The oldest-known onium ion, and the namesake for the class, is ammonium , the protonated derivative of ammonia .
N
any salt in which the positive ion (onium ion) is formed by the attachment of a proton to a neutral compound, as in ammonium, oxonium, and sulphonium compounds 鎓盐
[chem]