35 2 · 8 · 18 · 7

Bromine, Br, element 35

Halogen· Period 4· Group 17· p-block

Configuration [Ar]3d104s24p5

Atomic weight
79.904Da
Phase
liquid
Density
3.1028g/cm³
Melting point
265.95K -7.2 °C
Boiling point
331.95K 58.8 °C
Electronegativity
2.96

Halogen element. Red volatile liquid at room temperature. Its reactivity is somewhere between chlorine and iodine. Harmful to human tissue in a liquid state, the vapour irritates eyes and throat. Discovered in 1826 by Antoine Balard. Description from mendeleev.

Back to the table
The outermost shell: the valence electronsThe inner shellsThe nucleus One bead for each electron, on the ring of its shell, counted from the nucleus out. The rings turn at their own pace; the model is Bohr's picture of the atom, which places electrons in shells but not on true orbits.

Atomic properties

4 of 5 fields have a value for bromine

Atomic weight The standard atomic weight. For an element with no stable isotope, the mass of its longest-lived isotope.
79.904Da
Source: mendeleev
Electron configuration
[Ar]3d104s24p5
Source: mendeleev
Electron configuration in full The electron configuration with the noble-gas core written out.
1s22s22p63s23p63d104s24p5
Source: Worked outfrom electron configuration
Electrons in each shell Counted from the electron configuration, from the first shell outward.
2 · 8 · 18 · 7
Source: Worked outfrom electron configuration

No data uncertainty of the atomic weight.

Screening of each subshell

Clementi's screening constants: how much of the nucleus's charge the other electrons hide from an electron in each subshell. What is left is the effective nuclear charge it feels.

SubshellScreening σEffective charge Z − σ
1s0.752934.2471
2s9.356625.6434
2p3.943631.0564
3s14.781520.2185
3p15.429219.5708
3d15.440919.5591
4s24.447210.5528
4p25.9729.028