Question

the fluoride anion always carries a charge of 1- true or false

I say true

Answer 1

True. The flouride anion is an ion of fluorine. Fluorine has only one oxidation state, of -1. WHY: Fluorine is the most electronegative element on the periodic table meaning that having an extra electron is very energetically favorable. (It "wants" one electron) In the F- ionic state it becomes iso-electronic with Neon, a noble gas. The noble gas characteristic, like non-re-activity and stability stem from the fact that it has all of its orbital completely filled. Thus it makes sense energetically that the F- ion formation would be favorable.