The electron configuration of a fluoride ion, f-, a.1s2 2s2 2p5 b. the same as that if a neon atom c.1s2 2s2 2p6 3s1. d. the same as that of a potassium ion

Option (A) is the correct answer.

Explanation:

Fluorine is a halogen atom and it belongs to group 7. Atomic number of fluorine is 9.

Therefore, electronic configuration of fluorine is .

Atomic number of neon is 10 and its electronic configuration is . Hence, we can see that electronic configuration of fluorine and neon are not the same.

Atomic number of potassium is 19 and its electronic configuration is which is not equal to electronic configuration of fluorine.      

Thus, we can conclude that out of the given options, electron configuration of a fluoride ion,F-,is 1S2 2S2 2P5.