Antimony Pentachloride / Antimony Pentachloride is a chemical compound with the formula SbCl5. It is colorless oil, but typical samples are yellowish due to impurities. Owing to its tendency to hydrolyze to hydrochloric acid, SbCl5 is a highly corrosive substance. Antimony Pentachloride hydrolyses readily to give hydrochloric acid: 2 SbCl5 + 5 H2O Sb2O5 + 10 HCl This reaction is suppressed in the presence of a large excess of chloride, owing to the formation of the hexachloroantimonate complexion.