Amphiprotic vs Amphoteric

[SophiaJenny3I]

Hi everyone! Just wanted to confirm the difference between amphoteric and amphiprotic. Amphiprotic means a molecule can ACT as both a proton donor and proton acceptor (using the Bronsted definition of acids and bases), while amphoteric means a molecule can REACT with both acids and bases. Is this correct? Thanks!

[Sami Siddiqui 1J]

Amphoteric means that a given substance can react with an acid or base, whereas amphiprotic just refers to the fact that a substance can either accept or donate a proton. Although they sound the same, note that not all amphoteric compounds necessarily have to gain or lose protons to act as both an acid or base. The best example I can find is in section 6D.3. Looking in that section, the book mentions that aluminum oxide (Al2O3) can act as an amphoteric compound and even shows reactions where Al2O3 reacts with an acid or base. However, the chemical formula itself doesn't contain H atoms, so it can't actually donate H+ protons from itself. Therefore, Al2O3 is amphoteric, but it isn't amphiprotic.