perchloric acid

chemical compound

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July 23, 2026

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Perchloric acid (HClO₄) is a fuming, corrosive, and strong acid. It is the most highly oxidized acid of chlorine and acts as a powerful oxidizing agent when heated. It is a salt or ester of perchloric acid. Perchloric acid can be made by the electrolysis of sodium chlorate, which is a crystalline salt (NaClO₄). The term "perchlor-" indicates a relatively large amount of chlorine, often in place of hydrogen. Hydrogen chloride (HCl), a related compound, is a gas at room temperature and pressure, and its solution in water is called hydrochloric acid.12345

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…it can be predicted that perchloric acid, HClO₄, is a stronger acid than sulfuric acid, H₂SO₄, which should be a stronger acid than phosphoric acid, H₃PO₄. For a given nonmetal central atom, the acid strength increases as the oxidation number of the central atom increases. For example, nitric acid, HNO₃,…
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…it can be predicted that perchloric acid, HClO₄, is a stronger acid than sulfuric acid, H₂SO₄, which should be a stronger acid than phosphoric acid, H₃PO₄. For a given nonmetal central atom, the acid strength increases as the oxidation number of the central atom increases. For example, nitric acid, HNO₃,…
Read More