Acetonitrile is a colorless liquid organic compound with the chemical formula CH3CN. It is the simplest organic nitrile, consisting of a methyl group attached to a cyano group. Acetonitrile is miscible with water and most organic solvents, making it a versatile solvent in various chemical processes. It is commonly used in organic synthesis, as a solvent in chromatography, and as a starting material for the synthesis of many compounds.