pyrosulfuric acid


py·ro·sul·fu·ric acid

P0690200 (pī′rō-sŭl-fyo͝or′ĭk)n. A fuming, dense, oily, colorless to dark brown liquid or hygroscopic crystalline solid, H2S2O7, the primary constituent of oleum, produced by adding sulfur trioxide to concentrated sulfuric acid, and used in petroleum refining and in the manufacture of explosives.