The Element Bromine
[Click for Isotope Data]
Atomic Number: 35
Atomic Weight: 79.904
Melting Point: 265.95 K (-7.2°C or 19.0°F)
Boiling Point: 331.95 K (58.8°C or 137.8°F)
Density: 3.11 grams per cubic centimeter
Phase at Room Temperature: Liquid
Element Classification: Non-metal
Period Number: 4 Group Number: 17 Group Name: Halogen
What's in a name? From the Greek word for stench, bromos.
Say what? Bromine is pronounced as BRO-meen.
History and Uses:
The only nonmetallic element that is a liquid at normal room temperatures, bromine was produced by Carl Löwig, a young chemistry student, the summer before starting his freshman year at Heidelberg. When he showed his professor, Leopold Gmelin, the red, smelly liquid he had produced, Gmelin realized that this was an unknown substance and encouraged Löwig to produce more of it so they could study it in detail. Unfortunately, winter exams and the holidays delayed Löwig's work long enough for another chemist, Antoine-Jérôme Balard, to publish a paper in 1826 describing the new element. Balard was credited with the discovery and named it after the greek word for stench, bromos. Today, bromine is primarily obtained by treating brines from wells in Michigan and Arkansas with chlorine.
Elemental bromine is a hazardous material. It causes severe burns when it comes in contact with the skin and its vapor irritates the eyes, nose and throat. Most of the bromine produced in the United States was used in the manufacture of ethylene dibromide(C2H4Br2), a chemical added to leaded gasolines that prevented the accumulation of lead compounds within the engine. With the discontinuation of leaded gasolines in favor of unleaded gasolines, the demand for bromine has been greatly reduced. Silver bromide (AgBr), a chemical used in photography, now accounts for the largest use of bromine. Other bromine compounds are used in fumigants, in flameproofing agents and in some compounds used to purify water. Tyrian purple, an expensive purple dye known to ancient civilizations, was produced from an organic bromine compound secreted from a sea mussel known as the murex.
Estimated Crustal Abundance: 2.4 milligrams per kilogram
Estimated Oceanic Abundance: 6.73×101 milligrams per liter
Number of Stable Isotopes: 2 (View all isotope data)
Ionization Energy: 11.814 eV
Oxidation States: +5, +1, -1
3s2 3p6 3d10