Si(HO)4

from The Collaborative International Dictionary of English v.0.48
Silicic \Si*lic"ic\, a. [L. silex, silicis, a flint: cf. F.
   silicique.] (Chem.)
   Pertaining to, derived from, or resembling, silica;
   specifically, designating compounds of silicon; as, silicic
   acid.
   [1913 Webster]

   {Silicic acid} (Chem.), an amorphous gelatinous substance,
      {Si(HO)4}, very unstable and easily dried to silica, but
      forming many stable salts; -- called also {orthosilicic
      acid} or {normal silicic acid}.
      [1913 Webster]
    

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