* Bromine's Electron Configuration: Bromine has 35 electrons. Its electron configuration is [Ar] 3d¹⁰ 4s² 4p⁵. It only needs one more electron to fill its outermost p orbital, making it more stable.
* Gaining an Electron: By gaining an electron, bromine achieves a full octet in its outermost shell. This makes the ion much more stable than the neutral atom.
* Formation of the Bromide Ion: The gained electron fills the 4p orbital, giving the bromide ion the same electron configuration as the noble gas krypton.
Here's a summary:
* Bromine atom (Br): Neutral, 35 electrons, electron configuration [Ar] 3d¹⁰ 4s² 4p⁵
* Bromide ion (Br⁻): Negatively charged, 36 electrons, electron configuration [Ar] 3d¹⁰ 4s² 4p⁶ (same as krypton)
The bromide ion is now more stable and less likely to react further. This is a common occurrence in chemistry, where atoms gain or lose electrons to achieve a more stable state.
