English Vocabulary Flash Cards - Chemical Formulas @ englishpdf.com and englishteststore.com File 142 K2 O2 potassium peroxide K2 O3 P potassium metaphosphate K2O3Si potassium silicate K2 O4 S dipotassium sulphate K2 O4 S potassium sulphate K2O7NS2 potassium nitrosodisulfonate K2[PtBr6] potassium hexabromoplatinate(IV) K2[Pt(CNS)6] potassium hexathiocyanoplatinate(IV)