Word Study
pyrosulphuric
CIDE DICTIONARY
pyrosulphuric, a. [Pyro- + -sulphuric.].
Pertaining to, or designating, an acid called also disulphuric acid ) obtained by distillation of certain sulphates, as a colorless, thick, oily liquid, H2S2O7 resembling sulphuric acid. It is used in the solution of indigo, in the manufacture of alizarin, and in dehydration. [1913 Webster]
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