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Tannic acid is a specific form of tannin, a type of polyphenol. Its weak acidity (pKa around 6) is due to the numerous phenol groups in the structure.
T 7064 (OTTOKEMI) Tannic acid ACS reagent grade, powder or solid Cas 1401-55-4 - used in the following processes synthesis of ferric tannate complexes by reacting with metallic iron.