

According to Brønsted-Lowry theory, an acid is a substance which can donate a proton (H+) to another compound and a base is a substance that accepts the proton from an acid
Example,
Hydrochoric acid (HCl) dissolve in water (H2O) and produce hydronium ions (H3O+) and chloride ions (Cl-).
HCl + H2O ↔ H3O+ + Cl-
In this chemical reaction, HCl acts as an acid which donates its proton to form Cl- ions. whereas, H2O acts as a base which accepts that proton to form H3O+. Therefore, we can say that acids and bases have unique properties which can distinguish between each other. Thus it is practically not feasible for an acid to become a base and vice versa.
