... grade), AP21 (1985), Top grade. Name: Gallic acid Chemical Name: 3,4,5-Trihydroxybenzoic acid Structural formula: Molecular formula & Molecular weight: C7H8O6 ... -water, slightly soluble in ether. 6.Technical data: Purity: % ≥99 Sulfate: ppm ≤10 Tannic acid test: ppm ≤1.0 ... strong products are:Tannic Acid(Pharmaceutical/Tech/Dyes/Food Grade),Gallic acid(3,4,5-Trihydroxybenzoic acid),Pyrogallol(1,2,3- ...