what is an ammonium ion ---Watch
But then, I thought: "the definition of a salt is that the H+ is replaced by a metal or AMMONIUM ion." In here, it is replaced by the NH3+?
salt : "any chemical compound formed from the reaction of an acid with a base, with all or part of the hydrogen of the acid replaced by a metal or other cation."
"In chemistry, a salt is an ionic compound that can be formed by the neutralization reaction of an acid and a base."
alkali conditions could give a salt, e.g. NH2CHRCOO-Na+ with the reagent NaOH
the textboom definition of a salt is confusing and quite limiting, i wouldnt worry about the definition of a salt. there is no replacement of H+ in either reaction, but either addition of H+ to the amino acid (acidic conditions) or donation of H+ (alkali conditions)