hyposulfurousacid

hy·po·sul·fu·rous acid (hī'pō-sŭl-fyo͝orʹəs, -sŭlʹfər-əs) n.

An unstable acid, H₂S₂O₄, known only in aqueous solution and used as a bleaching and reducing agent. Also called hydrosulfurous acid.

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