1s² 2s² 2p⁶

Here's how we arrive at that:

* Neutral Fluorine (F): Fluorine has 9 electrons. Its electron configuration is 1s² 2s² 2p⁵.

* Fluoride Ion (F-): Fluoride gains one electron to achieve a full octet and become more stable. This extra electron goes into the 2p orbital.

Therefore, the final electron configuration of the fluoride ion is 1s² 2s² 2p⁶.