Amphiprotic

In chemistry and physical sciences, a substance is described as amphiprotic if it can both donate or accept a amphoteric. Amphoteric substances, however, are not necessarily amphiprotic.

Example

A common example is the hydrogen carbonate ion, which can act as a base:

HCO₃^- + H₂O → H₂CO₃ + OH^-

Or as an acid:

HCO₃^- + H₂O → CO₃^2- + H₃O⁺

Thus, it can effectively accept or donate a proton. Water is the most common example of an amphiprotic substance:

Basic: H₂O + HCl → H₃O⁺ + Cl^-

Acidic: H₂O + NH₃ → NH₄⁺ + OH^-