<unk>  is a chemical compound with formula . It has been synthesized using non-aqueous solutions. It is assumed to be present when silicon dioxide (silica) dissolves in water at a millimolar concentration level.
Orthosilicic acid
Dichloroacetic acid
Fomite
Ferric maltol
Tetrachlorodecaoxide
Diatrizoate
Hermaphrodite 
Phospho soda