isopoly acid

chemical compound

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June 29, 2026

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An isopoly acid is a complex, oxygen-containing acid derived from a single inorganic acid by the elimination of water from two or more molecules. These are distinguished from heteropoly acids, which are formed when acid anhydrides condense with other acids.12

Isopoly acids are formed by amphoteric metals in specific oxidation states, such as vanadium, niobium, tantalum, chromium, molybdenum, and tungsten. The condensation reactions involve the formation of oxo bridges through the elimination of water. A simple example is the condensation of the chromate ion (CrO₄²⁻) to form the dichromate ion (Cr₂O₇²⁻).2

While isopoly acids are generally less stable than heteropoly compounds, they are important in various chemical contexts.2

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coordination compound
Isopoly and heteropoly anions
…acid anhydride, they are called isopoly acids, and their salts are called isopoly salts. The acid anhydrides also can condense with other acids (e.g., phosphoric or silicic acids) to form heteropoly acids, which can form heteropoly salts. The condensation reactions, which occur reversibly in dilute aqueous solution, involve formation of…
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…acid anhydride, they are called isopoly acids, and their salts are called isopoly salts. The acid anhydrides also can condense with other acids (e.g., phosphoric or silicic acids) to form heteropoly acids, which can form heteropoly salts. The condensation reactions, which occur reversibly in dilute aqueous solution, involve formation of…
Read More