Potassium \Po*tas"si*um\, n. [NL. See Potassa, Potash.]
  
         (Chem.)
   An Alkali element, occurring abundantly but
         always combined,
   as in the chloride, sulphate,
         carbonate, or silicate, in the
   minerals sylvite,
         kainite, orthoclase, muscovite, etc. Atomic
   weight 39.0.
         Symbol K (Kalium).
   [1913 Webster]

   Note: It is
         reduced from the carbonate as a soft white metal,
         lighter than water, which oxidizes with the greatest
         readiness, and, to be preserved, must be kept under
         liquid hydrocarbons, as naphtha or kerosene. Its
         compounds are very important, being used in glass
         making, soap making, in fertilizers, and in many drugs
         and chemicals.
         [1913 Webster]

   Potassium permanganate, the salt
         KMnO4, crystallizing in
 
             dark red prisms having a
         greenish surface color, and
      dissolving in water with
         a beautiful purple red color; --
      used as an oxidizer
         and disinfectant. The name chameleon mineral is
         applied to this salt and also to potassium
     
         manganate.

   Potassium bitartrate. See {Cream of
         tartar}, under Cream.
   
           [1913 Webster]