The electron configuration of bromine is 1s2 2s2p6 3s2p6d10 4s2p5, which can be shortened to [Ar] 4s2 3d10 4p5. The electron configuration indicates that bromine has a total of 35 electrons.
A bromine atom has two electrons in its first energy level, eight electrons in its second, 18 electrons in its third and seven electrons in its fourth. It has seven valence electrons, as indicated by the last part of the configuration, 4s2p5. Bromine has an atomic number of 35 and is part of the halogen group of elements and is considered a diatomic non-metal. Bromine's chemical symbol is Br.