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An oxoacid is defined as an acid that contains oxygen in its molecular structure along with hydrogen and at least one other element, usually a non-metal. These acids typically have the general formula where the acidic hydrogen atoms are bonded to oxygen atoms, and these oxygen atoms are in turn bonded to other elements—often containing central atoms such as sulfur, phosphorus, or nitrogen.

For example, sulfuric acid (H₂SO₄), phosphoric acid (H₃PO₄), and nitric acid (HNO₃) are all oxoacids. They are categorized based on the presence of oxygen within their structures, where the acidic properties arise from the hydrogen atoms that are attached to the oxygen atoms.

In contrast, while polyprotic acids can contain oxygen, the defining characteristic of polyprotic acids is their ability to donate more than one proton (H⁺) per molecule, rather than the presence of oxygen. Strong and weak acids refer primarily to their ionization and dissociation in water rather than their structural components. Some strong acids, such as hydrochloric acid (HCl), do not contain oxygen, while weak acids can be oxoacids as well.

Hence, the identification of an acid as an oxo