Question

What would be the most likely charge of an ion formed from an atom with the electron configuration:

1s22s22p5

+1

-1

+3

-3
I think A or B

Answer 1

Flourine.

Answer 2

If I remember the configuration correctly, then 5 is the valence electron. For atoms to achieve stable configuration, they must have 8 electrons in the valence shell. So this atom will need to add or remove the smallest number of electrons? 1 electron carries 1 negative charge.

Answer 3

The first complete set is 1s2, then you need a another set of 8, or octet from 2s2 sp5, which is 7 valence. It needs one to fill this valence. However, Flourine has only 9 protons so you get a negative one charge after gaining and additional electron when forming a bond with other atoms.