Products
Picric acid can be purchased as an open commodity (chemical) from appropriate distributors.
Structure and properties
Picric acid (C6H3N3O7, Mr = 229.1 g/mol) or trinitrophenol is present as pale yellow, shiny, odorless crystals with a very bitter taste. It is soluble in boiling water. Its salts are called picrates. Because of the nitro groups, picric acid is more acidic than phenol and has a pKa of 0.4 (!).
Effects
Picric acid colors proteins bright yellow. Caution: picric acid and especially its salts are explosive and acutely harmful in small amounts!
Use
Picric acid has been used as a reagent in microscopy, for chemical detection, as an explosive, and for dyeing, among other uses. Disposal at schools is strongly recommended. This is because old, dried picric acid can explode when struck, rubbed or heated.
