Phosphomolybdic acid, also known as dodeca molybdophosphoric acid or PMA is a component of Masson's trichrome stain. It is a yellow-green compound, freely soluble in water and polar organic solvents such as ethanol.
P 1738 (OTTO) Phosphomolybdic acid, 20 wt% in ethanol Cas 51429-74-4 - used as a reagent in thin layer chromatography for staining phenolics, hydrocarbon waxes, alkaloids and steroids.