Oxalic acid Oxalic acid Oxalic acid is an organic compound with the formula CHO. It is a colorless crystalline solid that forms a colorless solution in water. Its condensed formula is HOOCCOOH, reflecting its classification as the simplest dicarboxylic acid. Its acid strength is much greater than that of acetic acid. Oxalic acid is a reducing agent and its conjugate base, known as oxalate (), is a chelating agent for metal cations. Typically, oxalic acid occurs as the dihydrate with the formula CHO·2HO. It occurs naturally in many foods, but excessive ingestion of oxalic acid or prolonged skin contact can be dangerous.
Phosphomolybdic acid Phosphomolybdic acid Phosphomolybdic acid, also known as dodeca molybdophosphoric acid or PMA, is a yellow-green chemical compound that freely soluble in water and polar organic solvents such as ethanol. It is used as a stain in histology and in organic synthesis Phosphomolybdic acid is a component of Masson's trichrome stain. Phosphomolybdic is used as a stain for developing thin-layer chromatography plates, staining phenolics, hydrocarbon waxes, alkaloids, and steroids. Conjugated unsaturated compounds reduce PMA to molybdenum blue. The color intensifies with increasing number of double bonds in the molecule being stained. Phosphomolybdic acid is also occasionally used in acid-catalyzed reactions in