Periodic Table ~ bromine ~ Element ~ CAS 7726-95-6

bromine

Name	bromine
Symbol	Br
Atomic Weight	79.904
Atomic Number	35
CAS ID	7726-95-6
Group Number	17
Group Name	Halogen
Period Number	4
Origin of Name	Greek, bromos - "stench."
Year Discovered	1826
Discovery Credits	A. J. Balard at Montpellier, France and C. Lowig at Heidelberg in Germany.
Class	Non-Metallic
Color	Red-brown, metallic luster when solid
Standard State	Liquid at 77 F & 298 K
Description	Deep red, dense, sharp smelling liquid, Br₂. Compounds used in fuel additives, pesticides, flame-retardants, and photography. Bromine is recovered from sea water and oil field brines. Diagnostic tests: Bromine salts (along with F, Cl, and I) will give a blue color to flames when heated on a copper disk. Treatment of the salt with concentrated H₂SO₄ acid will effervesce with the evolution of a brown gas (Br₂). Bromine is always found associated with chlorine or iodine so a precipitate with AgNO₃ solution is white (AgCl), cream (AgBr), or yellow (AgI) depending on which anion predominates.