H2SO4

from The Collaborative International Dictionary of English v.0.48
Sulphionide \Sulph*i"on*ide\, n. (Chem.)
   A binary compound of sulphion, or one so regarded; thus,
   sulphuric acid, {H2SO4}, is a sulphionide.
   [1913 Webster]
    
from The Collaborative International Dictionary of English v.0.48
Sulphuric \Sul*phu"ric\, a. [Cf. F. sulfurique.]
   1. Of or pertaining to sulphur; as, a sulphuric smell.
      [1913 Webster]

   2. (Chem.) Derived from, or containing, sulphur;
      specifically, designating those compounds in which the
      element has a higher valence as contrasted with the
      sulphurous compounds; as, sulphuric acid.
      [1913 Webster]

   {Sulphuric acid}.
      (a) Sulphur trioxide (see under {Sulphur}); -- formerly so
          called on the dualistic theory of salts. [Obs.]
      (b) A heavy, corrosive, oily liquid, {H2SO4}, colorless
          when pure, but usually yellowish or brownish, produced
          by the combined action of sulphur dioxide, oxygen
          (from the air), steam, and nitric fumes. It attacks
          and dissolves many metals and other intractable
          substances, sets free most acids from their salts, and
          is used in the manufacture of hydrochloric and nitric
          acids, of soda, of bleaching powders, etc. It is also
          powerful dehydrating agent, having a strong affinity
          for water, and eating and corroding paper, wood,
          clothing, etc. It is thus used in the manufacture of
          ether, of imitation parchment, and of nitroglycerin.
          It is also used in etching iron, in removing iron
          scale from forgings, in petroleum refining, etc., and
          in general its manufacture is the most important and
          fundamental of all the chemical industries. Formerly
          called {vitriolic acid}, and now popularly {vitriol},
          and {oil of vitriol}.

   {Fuming sulphuric acid}, or {Nordhausen sulphuric acid}. See
      {Disulphuric acid}, under {Disulphuric}.

   {Sulphuric anhydride}, sulphur trioxide. See under {Sulphur}.
      

   {Sulphuric ether}, common anaesthetic ether; -- so called
      because made by the catalytic action of sulphuric acid on
      alcohol. See {Ether}, 3
      (a) .
          [1913 Webster]
    

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