English Vocabulary Flash Cards - Chemical Formulas @ englishpdf.com and englishteststore.com File 114 FeAsS iron arsenic sulfide or arsenopyrite FeBr3 · 6H2O iron(III) bromide hexahydrate FeCO3 siderite FeC2O4 iron oxalate FeC5O5 iron pentacarbonyl or pentacarbonyl iron FeC10H10 ferrocene FeCl3 iron(III) chloride FeCr2O4 chromite (ore)