hydrogen bromide

chemical compound

Written by

The Information Architects of Encyclopaedia Britannica

Last updated

June 24, 2026

Quick Summary

Hydrogen bromide (HBr) is a colorless, irritating gas that fumes in moist air. When dissolved in water, it forms hydrobromic acid, a strong acid similar in activity to hydrochloric acid. Bromine itself is a chemical element, a deep red liquid and a member of the halogen group. Bromine was discovered in 1826 and named for its bad odor. While bromine is rare in nature, it is found in compounds in Earth's crust, ocean water, and salt deposits. Bromine compounds have various uses, including flame retardants, soil pest control, and catalysts. Historically, bromides were used as sedatives, and silver bromide is crucial in photographic film. Hydrogen bromide serves as a reducing agent and catalyst in organic reactions.12

Summary created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

2 Britannica Sources

Ask Britannica AI about this topic

Britannica doesn't have a full article on this topic, so we've curated a list of our relevant coverage.

bromine
Production and use
…bromine compounds of significance include hydrogen bromide (HBr), a colorless gas used as a reducing agent and a catalyst in organic reactions. A solution of the gas in water is called hydrobromic acid, a strong acid that resembles hydrochloric acid in its activity toward metals and their oxides and hydroxides.
Read More
…bromine compounds of significance include hydrogen bromide (HBr), a colorless gas used as a reducing agent and a catalyst in organic reactions. A solution of the gas in water is called hydrobromic acid, a strong acid that resembles hydrochloric acid in its activity toward metals and their oxides and hydroxides.
Read More