Brine is acidified and chlorinated: Cl2 + 2 Br⁻ → Br2 + 2 Cl⁻; the Br2 is stripped from solution with steam or air and condensed.
Research Elements Br · atomic number 35 Halogen · period 4, group 17 [Ar] 3d10 4s2 4p5 Shells: 2, 8, 18, 7 Valence electrons: 7 in the outer shell (4s2 4p5) Green dots are the outer shell's s and p electrons. Softer green dots are the d electrons of transition metals, and the d and f electrons of lanthanides and actinides: they often take part in bonding, but not always. Grey dots are the core. Ground-state configuration from the NIST Atomic Spectra Database (A. Kramida, Yu. Ralchenko, J. Reader and the NIST ASD Team). Abundance is the mole fraction of the element found as that isotope on Earth; digits in parentheses are the uncertainty in the last digits. Masses and abundances from NIST, Atomic Weights and Isotopic Compositions (J. S. Coursey, D. J. Schwab, J. J. Tsai and R. A. Dragoset, National Institute of Standards and Technology).Bromine
Electrons
How it's obtained
Natural isotopes
Isotope Relative atomic mass Abundance 79Br 78.9183376(14) 0.5069(7) 81Br 80.9162897(14) 0.4931(7)