Hydrogen bromide is the diatomic molecule HBr. HBr is a gas at standard conditions. Hydrobromic acid forms upon dissolving HBr in water. Conversely, HBr can be liberated from hydrobromic acid solutions with the addition of a dehydration agent, but not by distillation. Hydrogen bromide and hydrobromic acid are, therefore, not the same, but they are related. Commonly, chemists refer to hydrobromic acid as “HBr”, and this usage, while understood by most chemists, is imprecise and can be confusing to the non-specialist.