gallic acid is an important component of iron gall ink

gallic acid (also known as 3,4,5-trihydroxybenzoic acid) is a trihydroxybenzoic acid with the formula c6h2(oh)3co2h. it is classified as a phenolic acid. it is found in gallnuts, sumac, witch hazel, tea leaves, oak bark, and other plants. it is a white solid, although samples are typically brown owing to partial oxidation. salts and esters of gallic acid are termed "gallates".

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