Antimony pentafluoride is a colorless thick liquid. It is a powerful oxidizing agent and very reactive. It can help fluorine to oxidize oxygen. This is not normal as oxygen normally oxidizes other things; it does not get oxidized. It can make very strong acids when mixed with hydrofluoric acid. It was used in the first reaction that used fluorides to make fluorine.
It is used to make very strong acids.
Antimony pentafluoride reacts with most chemical compounds. It is extremely corrosive.