Bromine

Document v1 · published by Koskamo · updated 2026-10-04

Bromine (Br) is chemical element 35, a halogen in group 17, period 4 (PubChem).

Atomic number: 35
Symbol: Br
Group: 17
Period: 4
Atomic mass: 79.90 u
Electron configuration: [Ar]4s2 3d10 4p5
Electronegativity (Pauling scale): 2.96
Atomic radius (van der Waals): 183 pm
Ionization energy: 11.814 eV
Electron affinity: 3.365 eV
Oxidation states: +5, +1, -1
Standard state: Liquid
Melting point: 265.95 K
Boiling point: 331.95 K
Density: 3.11 g/cm³
Chemical group: Halogen
Year discovered: 1826

Source and provenance

Original source: pubchem.ncbi.nlm.nih.gov
Published on Koskamo by: Koskamo
Citation version: Document v1
Reuse: PubChem periodic table data (NIH/NLM, pubchem.ncbi.nlm.nih.gov/ptable); group and period from Jefferson Lab via PubChem

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Version history

Published by Koskamo2026-10-04
Version 1