How many unpaired electrons are present in Ni+2?
2
The ground state electronic configuration of Nickel is:
[Ar]3d84s2
Nickel will lose two electrons from its valence shell to form Ni+2 ion. The electronic configuration of Ni+2 ion is:
[Ar]3d8
The way electrons of Ni+2 ion will get filled d- orbital is shown in the digram below:
There are two unpaired electrons present in the d orbital for Ni2+ ion.