Atomic number 35
Bromine
Halogen
In the real world
Quick facts
- Atomic mass
- 79.904
- Group
- 17
- Period
- 4
- State (STP)
- liquid
- Electronegativity
- 2.96
- Common ox. states
- -1, +1, +3, +5, +7
Properties
Electron configuration
[Ar] 3d¹⁰ 4s² 4p⁵
- Ionization energy
- 1139.9 kJ/mol
- Electron affinity
- 324.6 kJ/mol
- Melting point
- 265.95 K (-7.2 °C)
- Boiling point
- 332.00 K (58.9 °C)
How dangerous is it?
4/5 · Severe
One of only two elements that are liquid at room temperature. The deep red-brown liquid gives off toxic, choking fumes.
- CorrosiveImmediate
The liquid burns skin on contact, and the vapor burns the eyes and airways.
Poured only in a fume hood with gloves and goggles; stored sealed in glass.
- ToxicImmediate
Breathing the orange vapor irritates and damages the lungs.
Kept tightly sealed; any open use happens under strong ventilation.
How it bonds
Bromine forms one bond - Br⁻ in NaBr, single-bonded in CHBr₃ and HBr. Three lone pairs. The only nonmetal that is a liquid at room temperature (deep red, fumes pungently). Like chlorine, can swing positive (BrO₃⁻) when paired with oxygen.
