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A white crystalline compound, Na2S2O3, often prepared as a pentahydrate, used as a photographic fixing agent, as a bleach and antichlor, as an antidote for cyanide poisoning, and as an antifungal agent. Also called hypo1, hyposulfite, sodium hyposulfite.
a white, crystalline, water-soluble powder, Na2S2O3∙5H2O, used as a bleach and in photography as a fixing agent. Also called hypo, hyposulfite, sodium hyposulfite.