0 → amphoteric
1 having characteristics of both an acid and a base
An amphiprotic molecule (or ion) can either donate or accept a proton, thus acting either as an acid or a base.
Amphiprotic solvents have both protophilic and protogenic properties.
Since they can donate a proton, all amphiprotic substances contain a hydrogen atom.
A similar type of reaction, but in which no element changes oxidation number, is the acid-base disproportionation reaction observed when an amphiprotic species reacts with itself.
