Ion formation and unpaired e-

[Daniel_Frees_1L]

Do ions always form with such a configuration that there are the fewest possible unpaired e-?

When doing problem 2A.21 part d I took silver's ground state configuration and removed 1 5s e- to make the Ag+ ion, and thus had [Kr] 4d9 5s1 as my electron configuration. The book says the answer is [Kr] 4d10. Why is this?

[Iris Bai 2K]

When the d orbital can be half filled or completely filled, the electrons will try to fill the orbital instead of going to the s orbital. It's similar to the Cr and Cu examples Dr. Lavelle gave in lecture.

[RachaelKoh3A]

To add on, this happens because when the d orbitals are half or fully filled the atom/ion will be more stable!