Final answer:
The amphoteric species among the given options is HPO4²-, which can act as both an acid and a base by either accepting or donating a proton.
Step-by-step explanation:
The question asks about the amphoteric nature of certain species. An amphoteric species is capable of acting as both an acid and a base. Among the given options - CO32-, NH4+, LiI, HPO42-, and HI - the compound that is amphoteric is HPO42-. This species can act as a Brønsted-Lowry base by accepting a proton from water to form H2PO4- and OH-, and can act as an acid by donating a proton to form PO43- and H2O, reflecting its amphiprotic character:
- HPO42-(aq) + H2O(l) → H2PO4- + OH-(aq)
- HPO42-(aq) + OH-(aq) → PO43- + H2O(l)