Halogen observed to react with hydrogen to form hydrogen halides. For fluorine, chlorine, and bromine, this reaction is in the form of: However, hydrogen iodide and hydrogen astatide can split back into their constituent elements. The hydrogen-halogen reactions get gradually less reactive toward the heavier halogens. A fluorine-hydrogen reaction is explosive even when it is dark and cold. A chlorine-hydrogen reaction is also explosive, but only in the presence of light and heat. A bromine-hydrogen reaction is even less explosive; it is explosive only when exposed to flames. Iodine and astatine only partially react with hydrogen, forming equilibria. All halogens form
Bromine pentafluoride Bromine pentafluoride Bromine pentafluoride, BrF, is an interhalogen compound and a fluoride of bromine. It is a strong fluorination reagent. BrF finds use in oxygen isotope analysis. Laser ablation of solid silicates in the presence of bromine pentafluoride releases O for subsequent analysis. It has also been tested as an oxidizer in liquid rocket propellants and is used as a fluorinating agent in the processing of uranium. Bromine pentafluoride was first prepared in 1931 by the direct reaction of bromine with fluorine. This reaction is suitable for the preparation of large quantities, and is carried out at temperatures over with