What is (a) A salt of what was formerly called hyposulphurous acid; a thiosulphate. [Obs.] (b) A salt of hyposulphurous acid proper called?

hyposulphite — (a) A salt of what was formerly called hyposulphurous acid; a thiosulphate. [Obs.] (b) A salt of hyposulphurous acid proper. (Webster's 1913.)

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