Bromine (Br)
Bromine (Br, element 35) is a halogen in group 17, period 4. Atomic mass 79.904, electron configuration [Ar] 3d¹⁰ 4s² 4p⁵, uses and facts.
About Bromine
Bromine is a halogen with the symbol Br and atomic number 35. It is a liquid at room temperature, and it sits in group 17, period 4 of the periodic table. Bromine was discovered in 1826 by Antoine Jérôme Balard.
Bromine key facts
- Atomic number: 35
- Symbol: Br
- Atomic mass: 79.904 u
- Category: halogen
- Group: 17
- Period: 4
- State at room temperature: liquid
- Electron configuration: [Ar] 3d¹⁰ 4s² 4p⁵
- Electronegativity (Pauling): 2.96
- Melting point: 265.8 K (-7.35 °C)
- Boiling point: 332 K (58.85 °C)
- Density: 3.122 g/cm³
- Common oxidation states: −1, 0, +1, +3, +4, +5, +7
Electron configuration
The electron configuration of bromine is [Ar] 3d¹⁰ 4s² 4p⁵. The part in brackets is the noble gas core; the rest shows how the outer electrons fill their subshells. Bromine has 7 valence electrons.
Uses of bromine
- Flame retardants
- Photography
- Pesticides
Did you know?
One of only two elements liquid at room temperature (the other is mercury). A red-brown fuming liquid.
Other elements in group 17 and neighbours
Frequently asked questions
What is the atomic number of bromine?
The atomic number of bromine is 35, which means every bromine atom has 35 protons.
What is the electron configuration of bromine?
The electron configuration of bromine is [Ar] 3d¹⁰ 4s² 4p⁵.
What group and period is bromine in?
Bromine is a halogen in group 17, period 4.
What state is bromine at room temperature?
Bromine is a liquid at room temperature.
What is bromine used for?
Bromine is used for flame retardants, photography, pesticides.