Bromine Bromine Bromine is a chemical element with symbol Br and atomic number 35. It is the third-lightest halogen, and is a fuming red-brown liquid at room temperature that evaporates readily to form a similarly coloured gas. Its properties are thus intermediate between those of chlorine and iodine. Isolated independently by two chemists, Carl Jacob Löwig (in 1825) and Antoine Jérôme Balard (in 1826), its name was derived from the Ancient Greek βρῶμος ("stench"), referencing its sharp and disagreeable smell. Elemental bromine is very reactive and thus does not occur free in nature, but in colourless soluble crystalline mineral halide salts,
Chemistry: A Volatile History all the elements in their order: Notice carbon and silicon are in Group IV and the volatile gases fluorine, chlorine and bromine are in Group VII. Mendeleev was sufficiently confident in the layout of his table that he was willing to leave gaps for unknown elements to make the pattern fit – believing other elements would later be discovered that filled the gaps. So, for Mendeleev to be vindicated, the gaps needed to be filled, and luckily, in 1859, new instrumentation had been developed for discovering elements. Robert Bunsen knew that when certain elements burned in the flames of his