The silicic acid formula, also called as Orthosilicic acid formula or Monosilicic acid formula is explained in this article. It is a silicon oxoacid and conjugate acid of a trihydrogensilicate. The molecular formula of Silicic acid is H4O4Si.Orthosilicic acid is a compound of hydrogen, oxygen and silicon. It is mainly found in borage. It will be obtained as an unstable solution in water.