pyrosulfuric acid

noun

py·​ro·​sulfuric acid

"+…-

: an unstable, crystalline acid H₂S₂O₇ that is usually handled commercially as a thick oily fuming liquid, that is formed by the union of sulfur trioxide with sulfuric acid, that is a chief component of fuming sulfuric acid, and that is converted to sulfuric acid when mixed with water

called also disulfuric acid

compare oleum

Word History

Etymology

International Scientific Vocabulary pyr- + sulfuric

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