pyrosulfuric acid

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Related to pyrosulfuric acid: Fuming sulfuric acid

py·ro·sul·fu·ric acid

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.