Hydrogen Bromide

Hydrogen bromide is the diatomic molecule HBr. Under standard conditions, HBr is a gas, but it can be liquified. The aqueous solution hydrobromic acid forms upon dissolving HBr in water. Conversely, HBr can be liberated from hydrobromic acid solutions upon the addition of a dehydration agents. 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.
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Noun
1. a colorless gas that yields hydrobromic acid in solution with water
(hypernym) bromide

chemical formula HBr, hydrogen bromide is a toxic, corrosive gas with a TLV of 3ppm. Hydrogen bromide has a strong irritating odor and is irritating to lungs, skin and eyes. Hydrogen bromide is used as an etch gas.