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|Jmol 3D image||Interactive graph|
|Molar mass||170.12 g/mol|
|Appearance||White, yellowish-white, or
pale fawn-colored crystals.
|Density||1.694 g/cm3 (anhydrous)|
|Melting point||260 °C (500 °F; 533 K)|
|1.19 g/100 mL, 20°C (anhydrous)
1.5 g/100 mL, 20 °C (monohydrate)
|Solubility||soluble in alcohol, ether, glycerol, acetone
negligible in benzene, chloroform, petroleum ether
|Acidity (pKa)||COOH: 4.5, OH: 10.|
|Safety data sheet||External MSDS|
|Lethal dose or concentration (LD, LC):|
LD50 (Median dose)
|5000 mg/kg (rabbit, oral)|
|Benzoic acid, Phenol, Pyrogallol|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
|what is ?)(|
Gallic acid is a trihydroxybenzoic acid, a type of phenolic acid, a type of organic acid, also known as 3,4,5-trihydroxybenzoic acid, found in gallnuts, sumac, witch hazel, tea leaves, oak bark, and other plants. The chemical formula is C6H2(OH)3COOH. Gallic acid is found both free and as part of hydrolyzable tannins. The gallic acid groups are usually bonded to form dimers such as ellagic acid. Hydrolysable tannins break down on hydrolysis to give gallic acid and glucose or ellagic acid and glucose, known as gallotannins and ellagitannins respectively.
Gallic acid is commonly used in the pharmaceutical industry. It is used as a standard for determining the phenol content of various analytes by the Folin-Ciocalteau assay; results are reported in gallic acid equivalents. Gallic acid can also be used as a starting material in the synthesis of the psychedelic alkaloid mescaline.