Bicarbonate demonstrates amphiprotic behaviour because it can react with water as:

1. An amphiprotic species can both donate and accept a proton. 2. Two separate equations are needed to show bicarbonate's behaviour. 3. The first represents the reaction of bicarbonate as an acid with water as a base. 4. The second represents the reaction of bicarbonate as a base with water as an acid. 5. Water itself is amphiprotic too, which is why it can take either role. _Source: OpenStax Chemistry 2e (CC BY 4.0), Ch 14 'Acid-Base Equilibria', sections 14.1-14.7_