Webster's 1828 Dictionary
HYPOSULPHUROUS
a.Hyposulphurous acid is an acid containing less oxygen than sulphurous acid. This acid is known only in combination with salifiable bases.
Webster's 1913 Dictionary
HYPOSULPHUROUS
Hy `po *sul "phur *ous, a. Etym: [Pref. hypo- + sulphurous. ] (Chem. )
Defn: Pertaining to, or containing, sulphur, all, or a part, in a low state of oxidation. Hyposulphurous acid. (a ) Thiosulphuric acid. [Obs. ] (b ) An acid, H2SO2, obtained by the reduction of sulphurous acid. It is not obtained in the free state, but in an orange-yellow water solution, which is a strong reducing and bleaching agent. Called also hydrosulphurous acid.
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