No, H2PO3 cannot be both an acid and a base at the same time. Acidity and basicity are opposing properties in chemistry. H2PO3 is an acid because it can donate protons (H+ ions) when dissolved in water. It can also accept protons, but its acidic properties are more dominant in aqueous solutions. Acids and bases are defined based on their behavior in chemical reactions, their ability to donate or accept protons, and their pH values. A substance cannot simultaneously display both acidic and basic characteristics.