hydrosulfurous acid

noun

hy·​dro·​sulfurous acid

"+…-

: an unstable acid H₂S₂O₄ known only in aqueous solution formed by reducing sulfurous acid or in the form of salts

—not used scientifically

called also dithionous acid, hyposulfurous acid

Word History

Etymology

hydrosulfurous International Scientific Vocabulary hydr- + sulfurous

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