Based on the Bronsted-Lowry mechanism of proton transfer, which of the following chemical species ac — Ionic Equilibrium Chemistry Question

💡 Solution & Explanation

A Bronsted acid must possess at least one donatable proton ($H^+$). Both the oxide ion ($O^{2-}$) and the carbonate ion ($CO_3^{2-}$) completely lack hydrogen atoms, meaning they physically cannot donate a proton; they can only accept protons (acting as bases). $HCO_3^-$ is amphiprotic (can donate or accept). $H_3O^+$ acts purely as a Bronsted acid in water.