Question

What is the electron configuration of Ni2+? How many valence electrons does this ion have?

Answer 1

Nickel has 28 electrons, its electron configuration is:

`1s^22s^22p^63s^23p^64s^23d^8`

Ni2+ has lost 2 electrons, which means that the resulting configuration would be:

`1s^22s^22p^63s^23p^64s^23d^6`

Nevertheless, since 4s electrons are further from the nucleus, they are lost resulting in a more stable ion, then, the actual configuration of Ni2+ is:

`1s^22s^22p^63s^23p^63d^8`

It means that this ion has 16 valence electrons.