disulphate

from The Collaborative International Dictionary of English v.0.48
Disulphate \Di*sul"phate\, n. [Pref. di- + sulphate.] (Chem.)
   (a) A salt of disulphuric or pyrosulphuric acid; a
       pyrosulphate.
   (b) An acid salt of sulphuric acid, having only one
       equivalent of base to two of the acid.
       [1913 Webster]
    

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