Bromine
Bromine (溴, symbol Br) is chemical element number 35, a Halogen in period 4, group 17 of the periodic table, with a standard atomic weight of about 79.904. Reddish-brown liquid at room temperature. One of only two liquid elements.
Properties
| Atomic number | 35 |
|---|---|
| Symbol | Br |
| Atomic mass | 79.904 u |
| Category | Halogen |
| Period | 4 |
| Group | 17 |
| Electron configuration | [Ar] 3d¹⁰ 4s² 4p⁵ |
| Electronegativity | 2.96 |
| Covalent radius | 120 pm |
| Density | 3.122 g/cm³ |
| Melting point | 265.8 K |
| Boiling point | 332 K |
| Discovery | Antoine Jérôme Balard, 1826 |
Overview
Reddish-brown liquid at room temperature. One of only two liquid elements. Bromine (Br) holds position 35 in the periodic table, a Halogen in period 4, group 17. As a halogen it is a reactive nonmetal that readily gains one electron to form a −1 ion.
Its electron configuration is [Ar] 3d¹⁰ 4s² 4p⁵, with 7 electrons in the outer shell, and an electronegativity of about 2.96 (Pauling). Around 25 °C it is usually a liquid (a very low melting point); it melts near 265.8 K (-7.3 °C), boils near 332 K (58.9 °C), has a density around 3.122 g/cm³.
In industry and daily life it turns up in Medical / Pharma and Structural / Alloys. On the safety side, it carries a high hazard rating. It was first described by Antoine Jérôme Balard in 1826. Browse elements of the same category in the browse view.
Electron shells
Electrons per shell: 2 · 8 · 18 · 7
Main uses
- Medical / Pharma
- Structural / Alloys
Hazard
Compounds containing Bromine
No compounds in this knowledge base contain Bromine yet.
Data sources
Atomic mass uses IUPAC (CIAAW) standard atomic weights; the covalent radius is from Cordero et al. (2008). Verify on the RSC Periodic Table, PubChem and Wikipedia. Educational reference only.