Hydrogen bromide


Hydrogen Bromide, HBr, is a toxic and flammable gas.

Physical and chemical properties

Physical state: Liquefied gas
Molecular weight: 81 g/mol
Smell: Pungent
Appearance/color: colorless


Hydrogen bromide is used:

  • in organic synthesis reactions, to add bromine atoms to molecules (e.g. alkali or alcohols); the chemical species obtained from these reactions are intermediate substances of pharmaceutical products;
  • as catalyst in the hydrocarbon alkylation;
  • for the production of inorganic bromides;
  • for the plasma etching of polysilicates, in the semiconductor fabrication cycle.

Stability and reactivity

It reacts with the major part of metals in the presence of humidity releasing hydrogen, an extremely flammable gas.
Combined with water, it causes rapid corrosion of some metals.
It reacts with water to form corrosive acids.
It can reacts violently with alkali.