Electron-Configuration Diagram for Bromine

The Electron-Configuration Diagram for Bromine 

Bromine's atomic number 35 identifies it as having 35 electrons in its shell. Argon is determined to be bromine's short-hand element based on counting backwards on the periodic table starting from bromine. Bromine's number of valence electrons can be found by subtracting argon's electron count(18) from bromine's electron count(35): 35-18=17. Bromine has 17 valence electrons. See the the orbital-filling diagram in figure 3. In this case, the valence shell is written as 4s23d104p5  Any sublevels filled after the 4s and before the 4p in the valence shell, namely the 3d¹⁰, are included in the valence shell portion of the electron-configuration diagram. The 18 electrons not in the valence shell are in the kernel. The electron-configuration diagram in figure 3 for bromine is [Ar]4s23d104p5 .

© Pat Thayer 2014-2016