[W/K] :: Nitric anhydride

  Nitric \Ni"tric\, a. [Cf. F. nitrique. See Niter.] (Chem.)
     Of, pertaining to, or containing, nitrogen; specifically,
     designating any one of those compounds in which, as
     contrasted with nitrous compounds, the element has a higher
     valence; as, nitric oxide; nitric acid.
     [1913 Webster]
  
     Nitric acid, a colorless or yellowish liquid obtained by
        distilling a nitrate with sulphuric acid. It is powerfully
        corrosive, being a strong acid, and in decomposition a
        strong oxidizer.
  
     Nitric anhydride, a white crystalline oxide of nitrogen
        ({N2O5), called nitric pentoxide, and regarded as the
        anhydride of nitric acid.
  
     Nitric oxide, a colorless poisous gas ({NO) obtained by
        treating nitric acid with copper. On contact with the air
        or with oxygen, it becomes reddish brown from the
        formation of nitrogen dioxide ({NO2, also called nitric
        dioxide or nitric peroxide).
        [1913 Webster]