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35Br

Element 35

Bromine

Halogens

Bromine (Br) is in the p-block of the periodic table — group 17, period 4.

Bromine (from Ancient Greek:βρῶμος, brómos, meaning "stench") is a chemical element with symbol Br, and atomic number 35.

Key data

Atomic number
35
Atomic mass
79.904 u
Group / Period
17 / 4
Block
p-block
Phase at STP
Liquid
Density
3.1028 g/cm³
Melting point
-7.3 °C
Boiling point
58.9 °C
Electron configuration
[Ar] 3d10 4s2 4p5

Periodic table block

Bromine is in the p-block (group 17, period 4). Elements land in the p-block when their highest-energy electrons fill a p subshell — this region holds most nonmetals, the metalloids, and the metals on the right of the table.

s-blockp-blockd-blockf-block

New to this? Periodic table blocks explained: s, p, d, and f

Common uses

  • Flame retardants
  • Photographic film
  • Pool sanitizers

Discovery

Year: 1826

Discovered by: Antoine Jérôme Balard

Frequently asked questions

What is the atomic number of Bromine?

Bromine has atomic number 35. Its symbol is Br and its atomic mass is 79.904 u.

What category of element is Bromine?

Bromine is classified as halogens. It sits in group 17, period 4 of the periodic table.

What block of the periodic table is Bromine in?

Bromine is in the p-block (group 17, period 4). Its highest-energy electrons occupy the p subshell — you can see this in its electron configuration, [Ar] 3d10 4s2 4p5.

What is Bromine used for?

Common uses of Bromine include: Flame retardants, Photographic film, Pool sanitizers.

When was Bromine discovered?

Bromine was discovered in 1826 by Antoine Jérôme Balard.

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